A/N: OK, so I thought this was originally going to be a one-shot, but it apparently needed to be a two-shot! Of course all the regular characters belong to the BBC, they just feed my imagination.

WE ARE A CONSTANT - PART TWO

Susan finished making the tea and looked at Sarah and the Doctor sitting at the table. They were looking at each other, but not saying anything. Sue looked over at Luke and motioned for him to come stand close to her. 'Why don't you call Clyde and see if he can meet you at the park or something?' she whispered to him.

He gave her a questioning glance and whispered, 'Why?'

'Because Mum and the Doctor need some time alone.'

'What about you?'

'Don't worry, I'm going to get out of here too.' She took over two cups of tea and sat one each in front of the Doctor and Sarah. 'Here you go,' she said aloud. 'You two are killing me with the silence and staring into each other's eyes, and I happen to know that you're not communicating, because I'm not picking it up, and I would.'

Sarah glanced up at her, 'Sorry Susan. This just all seems so surreal.'

Susan reached up and squeezed Sarah's shoulder. 'I understand, Mum.' She motioned for Luke to head out of the room. 'Luke is going to go meet up with Clyde, and I'm going to disappear for a bit.'

The Doctor looked from Susan to Luke as he left, but said nothing. Sarah looked up at Susan, then stood up to whisper quickly in her ear.

Susan nodded, 'Don't worry, I'll take care of it.'

Sarah reached up and cupped Susan's cheek with her hand. 'Are you all right?'

'Of course,' Susan said, smiling. 'This is what we do, right?' At that, she gave the Doctor a quick glance and headed out the room.

The Doctor and Sarah both watched as Susan left the room. 'Your children remind me of you, Sarah Jane.'

Sarah laughed as she sat back down. 'They're both amazing. Luke is learning everything so fast and is amazingly brilliant, despite his age. It causes him some awkward moments, but his friends help a lot. I've had some rocky times with Susan, just because of everything she's gone through, but I wouldn't trade any of that for the closeness we have now because of it.'

The Doctor reached out and took Sarah's hand in his. 'I've missed you, Sarah.'

Sarah looked down at their hands, 'Why are you really here, Doctor?'

'Can't I just come to see my best friend?'

'Thirty years after the fact? That doesn't sound like you at all.'

'Well, I really shouldn't be here.'

Sarah shook her head. 'You know you're crossing your own timeline and that's never a good thing.'

The Doctor stood up. 'You're right, this does bend more than a few laws.' As Sarah stood up, he wrapped her in a warm embrace, 'But it's worth every second. I'm sorry I couldn't come back for you, Sarah.'

She buried her head in his scarf, committing each sensation to memory. 'I understand. I don't have to like it, but I think I finally understand.'

He pulled back, 'I know I'll see you again, and I'm looking forward to that, but I don't know if you'll see me.'

'Sad thing is, I understand exactly what you mean.' She looked up at smiled at him. 'Take care of yourself, Doctor.'

'And you, my Sarah Jane.' He leaned over and kissed Sarah's forehead before quickly walking out of the kitchen and back up towards the attic and the TARDIS.

Sarah leaned against the table and sighed deeply before reaching up and wiping away a stray tear.

~!~!~!~

As Luke left to go meet Clyde, Susan walked into the attic, giving her mother and the Doctor some time alone. Susan thought long and hard about what she was going to need to do. She could sense the timelines getting out of whack even as the minutes progressed. She walked over to the TARDIS and affectionately patted the door. 'You know, old girl, don't you?' She smiled as she felt the familiar pulse from the TARDIS echo through her mind.

She heard the Doctor's footfalls coming up the landing, so she leaned against the TARDIS casually and folded her arms as the Doctor entered.

'Ah, Susan the soldier, what are you doing here?'

'We need to talk, Doctor.'

'About?'

She nodded back towards the TARDIS. 'In the TARDIS, away from any ears.'

The Doctor shook his head, 'I don't think so, here is fine.' Susan sighed and took out her own key, unlocked and quickly entered the TARDIS. The Doctor quickly followed her, an angry glare darkening his features. 'How did you get a key to my TARDIS?' he demanded.

'You gave it to me. Part of the privilege of travelling with you. Not to mention the other reason, the main reason really.'

'What reason?'

Susan walked up to him and stared directly at him. 'These eyes look familiar?'

'What?'

'They're yours. Mum doesn't have blue eyes.'

'Harry does.'

Susan raised an eyebrow to look at him. 'Yes, he does, but he can't tell you this.' She shot a thought in his direction.

The Doctor took in her expression, posture and attitude. She shot a second thought in his direction causing him to take a physical step back. 'I did nothing of the sort!' he exclaimed defensively.

'C'mon Doctor. You abandoned Sarah knowing full well she was pregnant,' Susan's tone wasn't one of anger, just stating the fact.

The Doctor dropped his head for a moment before looking back up at Susan, his voice taking a defeated tone, knowing she was at least partially right. 'I suspected, although I never knew for sure. I saw things in the Matrix on Gallifrey. I couldn't come back right away, but I needed to see her.' He walked up to Susan and put a tentative hand on her arm. 'And I needed to see if I was right.'

Susan smiled gently. 'You were, and here I am.'

The Doctor reached out and used his index finger under Susan's chin to turn her face up towards his, looking into her eyes, studying all her features before resting his hands on her shoulders. 'Have you had a good life, Sue?'

She nodded, 'I have. Harry has been an amazing father to me.'

'Come with me, Sue. Give me the opportunity to get to know you.'

She shook her head sadly. 'I can't, Doctor. You've crossed your own timeline and we can't change what's to come. You can remember coming here, seeing Sarah, even meeting Luke and thinking that he's yours. But you can't remember me. Our time isn't yet. If you remember me, things get all fouled up in the future.'

He pounced on one of her statements. 'We will have a time?'

'Oh yes, absolutely, but not yet and if you remember,' she paused, not wanting to think about the implications to her own past.

The Doctor finished the statement for her, 'I know, it will ruin everything that you've already gone through.'

'My past and everything that's happened would be for nothing.'

The Doctor smiled, 'Well, we can't have that, can we?'

Susan shook her head and was surprised when the Doctor quickly wrapped her in a large bear hug, resting his chin on the top of her head.

'This version of me never got to hold you as a child. I'm sorry I missed it. I could've taught you so much, Sue.'

Susan pulled back enough to look in his eyes and saw the raw emotion there. 'You did teach me so much, Doctor.' She couldn't help but have tears in her eyes as she looked at her true biological father for the first time. 'Even if you can't remember this moment, I will always treasure it because it gave me the opportunity to meet the version of you that Mum fell in love with. The one who loved her.'

'And I still do, if that means anything.'

'It does to me.' As they embraced as father and daughter for the first and last time, they each absorbed and memorised every second. Finally, Susan took a step back. 'It's time, Doctor. You need to forget me, forget this and move on.'

'I'm sorry I won't remember you the next time I see you, Sue.'

'It all eventually shakes out, over time. You'll just have to take my word on it for now.'

He nodded, 'Until we meet again, Susan.'

She took a couple of steps back towards the door without taking her eyes off of him. 'Mmm hmm,' she nodded. She headed towards the door, but then turned back at the last minute. 'Thank you,' she paused before adding, 'Dad.'

With that, she walked out the door and didn't turn back until the wheezing, groaning noise filled the room. She sighed deeply and let her head drop, not seeing Sarah enter the attic behind her.

Sarah walked over and wrapped an arm around Susan's shoulder as the TARDIS finished its dematerialisation. Sarah looked over and gave Susan's shoulders a squeeze as Susan brushed away a tear.

Susan rested her head on Sarah's shoulder. 'He's quite unforgettable, isn't he?'

Sarah laughed. 'Yes, you could certainly say that. That's one of the more outlandish versions of him I've ever known.' Quietly, she added, 'And I did love him.' Sarah sniffed to shake herself out of her own thoughts. 'Did you do what you needed to?'

Susan nodded, 'Yea. He'll go through with forgetting me like we discussed, but that should protect the timelines.'

'Good girl. I know that was tough.' Sarah wrapped her daughter in a warm hug.

Susan returned her mother's embrace. 'Oh yes. But the right thing to do isn't always easy. You taught me that, Mum.'

~!~!~!~