Note: This is going to be a collection of loosely related chapters centered around the scenario mentioned in the summary. The first snippet here doesn't start from the beginning of the incident, and I don't really plan on posting these snapshots in chronological order. Needless to say, Tinkerbell isn't in this chapter, but she definitely will show up in the future (as will David and others.)
If you have any scenarios or interactions you would like to see in this fic, I'm open to taking prompts. I am cross-posting this fic on AO3 and tumblr (ouatageregression dot tumblr dot com.)
I don't own Once Upon a Time.
Thanks for reading!

Rambunctious at Bedtime

Emma must have wandered into Henry's room after brushing her teeth because the two preteens are jostling each other on top of the boy's bed in the midst of a tickle fight. Even though she told the children to do the exact opposite of wind themselves up just before bedtime, Regina abates her irritation for a moment to watch the playful interaction from the hallway. She realizes that she has not seen Emma smile this brightly or laugh as loudly since before her magical de-aging. For once, she looks like a ten year-old girl instead of a brooding, stormy-eyed animal ready to pounce.

Henry topples on top of his mom, tickling her mercilessly over the x-men shirt Emma confiscated from Henry's drawer as sleepwear (she staunchly refused to put on any of the nightgowns Snow preferred, and Regina saw no point in fighting that battle, though Emma's opinion had given Snow another reason to pester the blonde girl. Emma didn't bother to acknowledge the other girl's goodnight before stomping up the stairs to brush her teeth.) Regina notes with renewed irritation that Emma seems to have discarded her pants somewhere in the seven steps between the bathroom and Henry's bedroom, since she is rolling around on their son's bed with her purple cotton underwear clearly on display where her shirt has risen up. Of course, Henry sees no harm in this, but Regina figures she'd better break it up before she makes herself even more uncomfortable with the situation.

"This is not at all what I meant when I told you two to get ready for bed," she admonishes as she walks into the room. She barely pays the children any mind as she crosses the floor to turn on Henry's nightlight, though her peripheral vision picks up the way Emma abruptly stops giggling before hastily shoving Henry off her.

"We're sorry, Mom," Henry says halfheartedly as he settles under the covers.

"Emma, it's time for you to go to your own room. Say goodnight to Henry, and get in bed, please. I'll be in to tuck you in soon," Regina instructs.
The girl looks up at Regina beneath a curtain of tangled blonde hair with those big, green eyes that match her mother's, but Emma appears to have no intention of doing as she's told just yet (somehow the Savior was more defiant as a child, much to Regina's bewilderment, since her adult-self seemed to live for pushing the former mayor's buttons.)

Now peering down at Henry's blue sheets, Emma timidly asks, "Can I stay here tonight?"

As much as Regina wants to let Emma shield herself from the hurricane that is Snow White, she realizes it will be best not to let the tension between the two fester. Perhaps rooming the two little girls together will cause more problems than it will solve, but for now they will all have to cope with the mansion's lack of a second guest bedroom. Besides, Henry kicks in his sleep and will no doubt push his mother off the mattress unintentionally during the night.

"No, Emma. You won't get any sleep in here with the two of you fighting for space, and Henry has school in the morning."

She really shouldn't let herself be manipulated into feeling guilty for refusing, but Regina takes one look at the deep frown etched into Emma's features, and the emotion squeezes her heart for a moment.

Instead of backing down, though, she tries to reassure, "Snow won't bother you about your clothing again. Or anything else for that matter." She should have guessed Snow White would be the troublemaker in the little trio tasked to her care.

At Regina's words, Emma snaps her head up, pointing her chin out and glaring slightly at her current guardian.

"You don't know that!" she nearly yells, prompting Regina to raise an eyebrow at the girl.

"Snow knows that any more inconsiderate words will get her into trouble, as do you, young lady. So I suggest you speak to me in a much calmer tone of voice." Reprimanding Emma means always walking a thin line between the girl's many reactions, but the former queen sees no reason to put up with more of Emma's uncurbed tongue after having fought countless verbal battles with her last year. A foolish part of Regina hopes once this spell wears off the adult Emma will remember some of the manners Regina is trying to impart upon her.

"Sorry," Emma mumbles (with minimal petulance before rolling off the bed, barely bothering the pull her shirt down once she is on her feet. Regina accepts the half-assed apology as progress in Emma's recognition of the older woman's authority, since twenty-four hours ago the girl wouldn't talk to her at all.

Never one to be left out of anything, Henry calls out to Emma, asking for a hug, before she can make a semi-dignified escape.

"Goodnight, Emma," he says happily once he feels Emma reciprocate the embrace.

"Goodnight," comes the quiet reply as the blonde pulls away, leaving the boy to snuggle his head fully in the pillow beneath his head as he waits for Regina to properly tuck him into bed.

Emma makes a show of not paying Regina any mind as she exits the room by dragging her feet and exhaling loudly in a slight huff.