Disclaimer: I do not own the song nor do I own the characters.

A/N: I'm not really sure where this idea came from, but here it is. It is technically a song-fic, so I'm going to end it with the title of the song. Let me know how I do. Enjoy!

I saw mommy kissing Santa Claus
Underneath the mistletoe last night
She didn't see me creep down the stairs to have a peek
She thought that I was tucked up in my bedroom fast asleep

"Lily! Lily! Wake up!"

Lily's eyes shot open with the feeling of someone shaking her bed and her along with it. "Addison! What are you doing?"

"I saw Mommy kissing Santa Claus!" Four-year-old Addison exclaimed.

Lily, still being groggy from sleep, blinked her eyes a few times. "You saw who doing what?"

"I saw Mommy kissing Santa Claus!" Addison repeated.

"Why were you even up?" Lily asked. She was ten, and while she still enjoyed Christmas and everything that came along with it, she no longer stayed up and waited for Santa Claus. She also knew that her dad was the Santa Claus that Addison claimed their mom had been kissing.

"I heard something," Addison explained to her older sister. "I thought it might be Santa. So I tiptoed out of my room and over to the stairs. Mommy was standing under the mistletoe and she was kissing Santa!"

"Are you sure Santa wasn't kissing her?" Lily teased.

Little Addison rolled her blue eyes. "What does it matter? There was still kissing going on!"

Lily tried not to laugh. She couldn't imagine that her mom and dad would let Addison catch them kissing. Besides, her sister wasn't the quietest person in the world and Lily was sure her parents would have heard Addison coming to peek downstairs. In fact, that's probably what they were banking on if her dad was dressing up as Santa Claus again. The last time he had done that was when she was around six.

"Are you sure they were actually kissing, Addison?" Lily asked.

Addison fisted her hands and put them on her hips in an affronted gesture. "I know what kissing looks like!"

Again, Lily had to bite her lips to keep from laughing. Aside from the blue eyes and blonde hair, she felt like she was being stared down by her mom. "Addison—"

Her sister didn't let her finish. "Come on! You come look! Then you can see I'm right."

Lily sighed. "Addison…"

"Come on!" Addison insisted.

Lily groaned but pushed her warm bedclothes back. She knew she wouldn't get a moment of peace until Addison got what she wanted.

Then I saw mommy tickle Santa Claus
Underneath his beard so snowy white
Oh, what a laugh it would have been
If daddy had only seen
Mommy kissing Santa Claus last night.

"Be quiet," Addison whispered to Lily as they started towards the stairs.

This time Lily was the one who rolled her eyes. Addison was telling her to be quiet? Usually she was the one who had to remind Addison! Still though, she made the motion of zipping her lips and throwing away the key.

Addison tiptoed to the top of the stairs and then made a "come here" motion with her pointer finger. When Lily reached her, Addison pointed down to their parents.

"You'd better not eat anymore of those cookies," Della teased patting Perry's stomach over the Santa suit.

Perry waved off her concern. "They're just pillows."

Della burst out laughing. "Maybe, but it won't stay that way."

Lily glanced over at Addison. After all, she was only four and she should get a few more years to believe in Santa. If she thought the plumpness of this man was pillows, she might not think he was Santa. Her dad wasn't doing a great job of disguising his voice either. Seeing Addison though, Lily could tell she did believe the man down there was Santa.

Perry backed up and purposefully stood under the mistletoe.

Della smirked and pointed above his head. "Look where you are."

"Oh, dear," Perry sighed. "Looks like you're just going to have to kiss me again."

Della tried to hold in her smile. "You'd better be careful. I have a husband upstairs who would be very angry if he came down here and saw me kissing you."

"Come on," Perry cajoled. "I am Santa after all."

Della shook her head in amusement, but agreed. She went over and began to kiss him.

Lily raised her eyebrows and Addison glared. She then whispered, "I'm going to wake up Daddy!"

Lily clamped her hand down on Addison's shoulder and steered her into the nearest room, which just happened to be the bathroom. She shut the door quietly behind her. "Addison, I wouldn't tell Dad if I were you." Lily wasn't about to let Addison walk into their parents room and find the bed empty.

"Why not?" Addison questioned. "Shouldn't he know that Mommy is kissing someone else?"

"Normally I would say yes," Lily admitted. "But this is Santa. He's here one night a year. Give them a break."

Addison shook her head. "I'm not buying it. Daddy needs to know."

Lily racked her brain. What would her dad say in a situation like this? "Addison, what does Mom always tell us not to do?"

"She tells us not to do a lot of things," Addison reminded Lily.

Lily forced herself to not roll her eyes. "When Dad's not working or when we wake up before him, what aren't we supposed to do?"

"Wake him up," Addison said.

"Right," Lily agreed. "Now, if we do something Mom tells us not to do, we're being naughty, right?"

Addison nodded her agreement.

"And what did Dad tell us Santa does to naughty little girls?" Lily asked.

"He brings them lumps of coal," Addison replied. "But Daddy said that wouldn't happen to us because we're not naughty little girls."

"No, we aren't," Lily concurred. "But if we wake Dad up…"

Addison filled in the blank in her head: we will get lumps of coal. "But Lily, the presents are already under the tree!"

"But Santa is still here," Lily reminded her little sister. "He could change his mind."

Lily could tell Addison was thinking about this twist in events. She hoped her argument had been enough to convince Addison, at least for tonight. She knew she wasn't as good as her father, Addison usually had her beat in that aspect. She couldn't win any argument where Addison was concerned. Lily mentally crossed her fingers.

"Maybe I should just wait and tell Daddy tomorrow?" Addison asked.

Lily smiled. She knew Addison phrased that as a question expecting Lily to agree. After all that trouble, Lily wasn't about to let her little sister down. Let her dad deal with it tomorrow. "I think that would be a great idea."

"But…"

"Addison!" Lily cut in. "Go to bed."

Addison looked like she was about to argue, but didn't. "Goodnight, Lily."

"Night, Addison." Lily waited until Addison was safely in her room before she turned toward hers. She had to stop for a minute and watch her parents again.

"One more kiss for Santa?" Perry asked.

"I have given too many kisses to Santa tonight already," Della said. "Santa doesn't get any more kisses." Della reached up and pulled his hat off his head and his beard down. "But I will give my husband as many kisses as he wants."

Lily wrinkled her nose as her parents started kissing yet again. Walking back to her bedroom she couldn't help but chuckle. She wondered what her dad would say to Addison tomorrow morning when she announced, "Daddy, I saw Mommy kissing Santa Claus!"

Well, what did you think? I realize there wasn't a whole lot of P/D, but I tried to get some in there. I find family plots fun though and I think it's incredibly cute that Perry would dress up as Santa for his kids. Tell me what you thought, please? Thanks for reading! Happy Holidays friends!