Warnings: Prompt, character death.

Spoilers: Through episode 2.5.

Disclaimer: I don't own Fringe or its characters.

Author's Note: Written for Death Bingo on Dreamwidth, prompt: Illness (sudden).

Carrying On

"It's a cold."

"Some cold to have chewed through your immune system, especially that quick. You didn't have any symptoms eight hours ago." Didn't have any symptoms when she slipped out of his bed in the hours before dawn, he thinks, but he doesn't add that, not when they aren't alone in the lab.

Her cough reduces the effectiveness of her glare, and he grins at her to hide his concern. She's too pale and her hands shake, just the smallest bit. He doesn't like the sound of her cough, either; it sounds like it's settled into her chest just a little too deeply.

"Walter, come here and take a look at her," he says, and the look she gives him promises payback, of the unpleasant variety.

Walter wanders over, studies Olivia from top to bottom. "You do not look well, Agent Dunham."

"A cold Walter." She crosses her arms across her chest, her expression as close sulky as Peter has ever seen. "Not that uncommon."

"Uncommon to you." Walter cocks his head, listens as Olivia coughs again. "I don't like the sound of that cough," he says, echoing Peter's silent assessment. "What other symptoms do you have? Exactly when did they start, and in what order?"

She rolls her eyes and glares at Peter again, but settles down to answer the questions.

~***~

"I hate your flu."

"Cold."

"Flu," he says, voice precise, if hoarse. "Influenza virus. Identified and categorized by Walter."

She can't help but smile at him, irritable though he is. She likes watching him sprawl on her couch, even when he's pale and clammy and miserable. Likes that he came to her, that she can take care of him the way he cared for her. "You get grumpy when you're feverish."

"Bite me."

She tilts her head slightly, and her smile broadens. "Really grumpy."

He starts to cough before he comes up with an appropriate response, and she lays a hand between his shoulder blades to steady him.

"Next time you get the flu, can we try not infecting me, too?" he asks, trying to sound irritable but mostly sounding plaintive.

She rubs his back, runs her thumb along the nape of his neck. "Next time, don't kiss me when I'm sick."

~***~

Olivia hangs up the phone, her face the careful blank of when she's hiding her feelings, but her eyes are shadowed. "Astrid's in the hospital, chest pain, trouble breathing. It— she's in serious condition. And the hospital is reporting dozens more cases like hers."

Walter's head comes up, eyes wide. "Serious condition? She was fine not five hours ago; the illness has advanced to that stage in that little time?" He doesn't sound surprised, only worried.

Olivia nods. "Apparently. We'll get you out there so you can take a look."

Peter waits until Walter has rushed off to confront Olivia. "What aren't you saying?"

She doesn't meet his eyes at first and now he knows something is really wrong. She fiddles with her phone, tucking it into her pocket resolutely before she lifts her head to look at him. "They're not sure if she's going to make it. If any of them are."

~***~

Walter only looks up from the microscope when Peter shoves the results of the DNA analysis into his hands. He studies the papers for a few minutes before nodding gravely. "As I suspected, this is the same strain that I isolated from you and Olivia a few days ago."

Olivia pushes up from the chair and paces, stalking from the computers to the lab benches and back again. "Why did it hit her so much more strongly than me and Peter? Why are we different?"

"Your immune system is hardier, by virtue of the experiments done on you as a child. Peter, perhaps, has some sort of partial immunity derived from being exposed to different strains in the first seven years of his life. For the others, their immune systems have never been challenged with anything quite like this. This is a unique variant, truly remarkable. Quite unlike anything I have ever seen. Possibly unlike anything this world has ever seen.

Olivia turns and stares at Walter, feeling herself growing cold. "This world? It came from elsewhere?"

"Perhaps, yes, a variant carried over from an alternate reality, a silent passenger between worlds. It may have been affected by the passage, however, just like a person would be. The version that ended up here could be quite different than the original."

"I brought it with me, on one of my jumps between worlds?"

He blinks, seeming to catch just what he's implying for the first time. "I... well, perhaps. There's no way to know, really. It could have been engineered. There's no telling."

"But it could have been me. I was sick first. I could have done this."

"The first one sick at Fringe Division. Not the first documented case." Peter shoots up and grabs her arm. "Don't do this to yourself, Olivia. It's not your fault."

She searches his face, can't tell if he's lying or not. He catches what he's doing and snorts. "I'll show you the damned data. I've been tracking the spread of this strain since you got the call about Astrid, trying to figure out its point of origin. And that origin was not with you."

"If I'd stopped the First Wave when I had the chance—"

"Or if I'd gone with you to see Nina and prevented the shapeshifter from making that call. Or if we hadn't stopped Jones from crossing over. Or if Walter hadn't taken me from the other side. Olivia, we can play this game for hours. There are thousands of variables that got us here, and every one of them doesn't rest on your shoulders."

She wants to believe, but can't stop the guilt that tightens in her chest.

~***~

Walter looks up from the lab bench for the twentieth time in ten minutes. "I'm sure we could help them," he repeats doggedly. "We need to go back and investigate the symptoms further."

Peter rolls his eyes. "I'm sure they don't need—"

"But I can get a better feel for her symptoms if I see her— see the patients for myself."

"Walter." Peter puts a gentle hand on his shoulder. "If you want to go visit Astrid all you need to do is ask."

Walter nods and turns to get his coat. Peter swears there are tears in his father's eyes although they're gone by the time he returns.

Astrid takes the intrusion with good grace, seemingly amused by Walter. She knows him well enough, Peter suspects, to realize that Walter's obsessive need for details about her symptoms is masking his genuine concern about her well being. She pokes at him with gentle humor between bouts of coughing, and Peter doesn't let Walter tire her out. They cede their place by her side to her parents when they rush in.

"She's not going to make it," Walter whispers mournfully as they enter the elevator. "Most of them won't."

~***~

They bury Astrid on a clear fall day, sun shining almost painfully bright and sky impossibly blue. Peter stands beside Olivia, face impassive, huddling in his jacket like it's forty degrees colder than the actual temperature.

It feels colder.

Olivia can't believe Astrid's gone. Assistant turned friend, who had taken her assignment to Walter's lab with good humor and infinite patience. Olivia doesn't know how they will ever manage without her.

When Olivia is called upon to speak, she stumbles through the appropriate words, but doesn't remember what they were when she finishes. Peter speaks next, and she listens more to his tone than what he says. Walter, when it's his turn, babbles, but it's heartfelt babble. Peter's hand finds hers, somewhere during his father's recitation, and she laces her fingers with his and holds tight.

At the end of his speech, Walter starts coughing, deep, racking coughs that are chillingly familiar. Peter's grip becomes painful and his eyes agonized.

~***~

"Walter—"

"No, Peter." Walter's voice drops to a whisper, pleading through his coughs. "Don't send me to the hospital. Please, son. Let me die here."

The hospitals are overcrowded. There's nothing they can do for him that Peter can't. "All right," he says finally, voice tight no matter how gently he tries to say the words. "If that's what you want."

Peter just watches, hands clenched, as Walter nods and shuffles off to the couch to sit down, pausing as another bout of coughing tears through him. It's his blunt acceptance of the inevitable that guts Peter. He stares at the man that he's both hated and loved, and can't imagine losing him.

Wonders how much more time he has before he does.

~***~

Peter doesn't say much, but his expression shifts from worried to resigned as his father's symptoms progress. Olivia watches him fuss over Walter and her heart aches. She's suddenly self-conscious, feeling like she's intruding on their private moments of pain. "Do you want me to go?"

"He'd want you there." Peter turns and grips her hands, his expression desperate. 'I want you there', his eyes say, and she squeezes back just as strongly.

Walter holds out longer than many, stubborn to the last. It's not until the early hours of the morning that he breathes out and never again breathes in. Olivia huddles close to Peter's side, her arm around his back and her forehead on his shoulder, while he bows his head and tears run down his face.

~***~

Olivia's eyes go unfocused, the way they always do when she peers between realities. Peter spends agonized minutes watching her. He's seen this before, had even tossed ideas back and forth with Walter about how and why it happened, and he is still afraid she won't come back to herself. Won't come back to him.

His throat tightens when he thinks about how fascinated Walter would be watching her, how he would be grabbing instruments and taking readings and ordering Astrid and Peter around. He ignores the stinging in his eyes and focuses on willing Olivia to open her eyes.

She snaps back into this reality with a gasp and her eyes immediately seek his. "It's not just us," she says starkly. "The other reality, they've been hit equally hard. Wherever this virus came from, it's decimating both of us."

"That's almost comforting," he says, wishing he could feel happier that the inevitable war between universes has been delayed.

She nods. "At least we'll have one less avenue of attack to worry about."

~***~

"...late yesterday afternoon... nothing we could do... still in critical condition..."

Olivia nods and says the right words, then lets the phone slip from her hand when she hangs up. She can't think past the scream that fills hear head and threatens to overwhelm her.

"Olivia? Olivia, what's wrong?"

She blinks and Peter's there, hands warm on her face as he peers into her eyes.

"Rachel... Rachel's dead. Yesterday. They don't know if Ella's going to make it. I didn't even know they were sick; last I talked to them they were fine, holed up for the duration. Why didn't I know they were sick? Why didn't they tell me?"

She realizes she's shaking and tears are pouring down her face. He pulls her against him and she lets her last pretenses of control unravel. He doesn't try to comfort her with meaningless protestations that everything's going to be all right, doesn't say anything, but the warmth of his arms around her and his hands in her hair tell her she's not alone.

~***~

"Ella? Honey?" Olivia perches next to her, eyes glued to her face, and brushes damp strands of hair away from her cheek. Ella is in one bed of dozens in the cafeteria that's been converted into a hospital ward, one of many impromptu wards erected around the city.

Forty percent of the population is sick, worldwide. They expect seventy percent will catch the virus before this is over, and only anticipate three quarters of those to survive. As one of the few who are immune and reasonably healthy, there are a thousand tasks Peter should be doing to help the city through the disaster. And he will, right after he makes sure one deeply grieving woman who means a hell of a lot more to him than anyone else doesn't take on one too many burdens and shatter.

~***~

Olivia wakes from a restless doze when Peter shakes her shoulder. Her heart constricts and she searches his face, not daring to look at Ella.

He smiles, a tired smile but one tinged with the first glimmer of hope in days. "Her fever's broken," he murmurs. "It's too early to say for sure, but..."

She barely dares to say the words. "She may make it?"

He nods and she drops her head, eyes stinging and hands clenched on her knees. She takes a deep, shuddering breath, then another. He rests a hand on her back in silent support.

~***~

By the time Ella's cries wake Peter up, Olivia's already out of the bed and in the girl's room. He follows, more slowly, to make sure he's not needed.

"It's only a nightmare, honey," Olivia murmurs, running gentle fingers through Ella's hair.

Ella nods, but her eyes are fearful. Olivia curls around her and croons softly until Ella falls back into a fitful sleep. Peter leans against the doorjamb, watching them, providing whatever silent support and comfort he can.

Ella's not healthy, not yet, but she's out of the hospital and getting better every day. The important thing is she's recovering. Most people didn't. Many countries never will. America got through it pretty damned well, considering, and even then the recovery effort will take decades.

Olivia untangles herself from Ella and gives Peter the ghost of a smile. Her eyes are sometimes still shadowed, and he catches remnants of guilt flickering across her face when she thinks he's not looking. He's grateful for Ella; without her niece to take care of Olivia would have worked herself into her grave trying to make up for perceived wrongs.

He catches her hand as she walks by, holding it tight. She looks up, surprised, and a real smile warms her face.

"Hey," she says, curling her fingers around his. She comes willingly when he tucks her against him, settling her head against his shoulder with a sigh.

"Hey." He nuzzles her hair and places a kiss on the top of her head. "She all right?"

"She will be," she says firmly. She moves far enough away to look him in the eyes and add more softly but with equal conviction, "We all will be."

Studying her face, a weight he didn't even know he was carrying lifts, and he feels lighter. Walking backwards, he leads her back to their bed.