Peter gave Wade's life stability. Stability to the point where he was able to pull his life together and raise his daughter the way a father should.
Peter and Wade raised Ellie as best as two assholes who knew nothing about children could, it went surprisingly well considering the circumstances.
With the aid of his newfound family, Peter's constant insistence and a couple of months of being REALLY REALLY good and SURPRISINGLY HELPFUL, Wade was finally admitted to the avengers. He was still a crude asshole, but he's gotten better to the point that people not only tolerate him, they're actually starting to begrudgingly grow fond of him.
While Deadpool and Black Widow had much differing opinions on the matter of subtlety they can often be found cleaning daggers together and discussing different means of assassination.
When Wade calls it "ASS-ASS-ination" her punch is mostly to hide the small smile on her face.
Tony is definitely the type of man who enjoys a crude joke every once in a while and Wade can actually be funny sometimes. They've banded together once or twice to play pranks on Steve.
Clint and Deadpool have worked together before and work together well now, some may even call them "bros".
Bruce still avoids Wade for the most part, but he appreciates how the former-mercenary is improving and how he acts around Peter. Its actually pretty cute the way Wade leans his head on Peter's shoulder when they sit next to each other, or how Peter has to qualms about sitting on Wade's back whenever the former-merc hogs the couch.
Steve is starting to see Wade's humanity. He's glad for him and considered Wade to be annoying, but a worthy comrade.
Wade tries to teach Thor pop culture.
The Avengers all knew that Wade had a daughter but it was in a distant sort of way.
Wade couldn't go on a mission because his daughter had a soccer game. Ellie had a dance recital. Ellie is going to girl-scout camp (Tony ordered a massive amount of girl-scout cookies from the girl). Sometimes the merc-turned-hero would remark about something cute Ellie did. When they traveled Wade would always pick up a souvenir for her at a street vendor.
They all sent birthday and Christmas gifts to her of course, and Steve once signed a plastic model of his shield for her when Wade brought it in, but they were a step-removed from her life. It was necessary for her to have a normal childhood. Wade didn't even carry a picture of her, too much of a security risk.
Among all of them it was probably Black Widow who had the most interaction with the girl. Peter and Wade would always chicken out whenever Ellie was having "girl problems" and one of them would always frantically call Natasha.
In retrospect this probably wasn't the smartest idea, because most of her advice to the child involved punching, stabbing or subterfuge.
Ellie was sent to the principle's office more than once because of aunty Natasha's advice.
So it was a surprise for everyone when the child suddenly showed up at the tower. Apparently it was "take your daughter to work day" at Ellie's school.
Which meant there was a small curly-haired girl silently coloring in the conference room when Steve called a meeting.
Tony was outside of the door to the conference room, flattening himself against the wall. When Bruce walked down the hall towards the conference room, Tony grabbed his arm and pulled him back before he could walk in.
"Hey hey hey Bruce" Tony pulled the other man to his side and whispered to him.
"What is it Tony?"
"There is a kid in the conference room."
Bruce peeks in at the child "I know what children look like Tony, what did you think it was an elf?"
"No WHY is there a kid in the conference room."
Bruce shrugged. Tony stroked his beard in thought.
"Old flames used to bring kids once in a while, claiming I was the dad and demanding child support, but how the hell did she get past security?"
"...Tony I think you're over-reacting."
"You're underreacting! There is probably a crazed one-night-stand loose in the building! This is way worse than Loki! Loki never demanded child support! this-"
Just then Natasha sauntered past them and into the conference room, despite Tony's whispered pleas.
"Hey kiddo…" she gently mussed Ellie's pigtail and sat next to the girl.
"I'm young, not deaf, you two can come out now." Ellie called out to the doorway without looking up from her sketchbook.
Tony and Bruce sheepishly looked into the conference room.
Just then Steve came in past Tony and Bruce into the conference room.
"Ok team we have a busy day of-"
His sentence was cut off by two skinny little arms wrapping around his waist in an ecstatic hug.
"EEEEE Captain America!" Ellie squealed "Thank you for signing my limited edition Captain America Shield! ALL the other kids in the neighborhood were SOOO jealous! I have all of your action figures! I have a Hawkeye figure too! Dad doesn't have a figure yet so I repainted a spiderman figure to look like him! Now I need another Spiderman figure... And its so cool to meet you!"
"Uhhhh…." Steve awkwardly pats Ellie's shoulders. "...Its nice to meet you too?" Why is there a kid in the conference room?
Natasha smiles condescendingly at Steve. "Awww how cute" she titters at him.
Steve gives her an unmistakable look of "Shut up" over Ellie's curly head.
Its then that Clint makes his entrance. "Hey guys what's the-" he spots Ellie hugging Captain America.
"Oh my gosh thats so cute" he gushes.
"I know right?" Natasha agrees while she takes a picture on her cell phone.
"Friends I heard that there was a meeting called, I have come forth as instructed-" Thor walks into the room and pauses at the sight.
"Good friend," Thor smiles teasingly at Steve and the preteen wrapped tightly around his midsection "Tis quite the belt thou wearest"
Steve glares at him.
Thor smiles wider.
Deadpool finally makes his appearance, entering the room with two cans of soda "Hey Ellie Tony is out of sierra mist so I got you Sprite and Mountain dew, Sprite is like sierra mist and-" He looks at his daughter hugging Captain America.
"Oh my gosh that is so fucking cute" He also pulls out his cellphone and takes a picture.
"You know her?" Bruce asks.
"YUP!" Deadpool bends down and presents his daughter with his arms, like a model presenting a prize on a game show "THIS IS MY KID!"
"Oh thank god theres no crazy one-night-stand in the tower" Tony whispers to himself.
"HIII!" Ellie Shrieks against Steve's perfectly toned abs.
Deadpool laughs fondly at his daughter. "Honey don't you think its time to let go of Mr. America?"
"Nope!" Ellie squishes her face against Steve's stomach "I've decided this is where I live now"
Clint is giggling so hard that his face is turning red.
"How you gonna eat baby-girl?" Deadpool puts his hands on his hips in a motherly way and tries his best not to giggle.
A thoughtful look passes over Ellie's face before a look of seriousness and determination. "There will be sacrifices" she says seriously "And you may have to hand-feed me"
"Phhht yeah ok" Deadpool covers his mouth with a hand. "Come on baby-girl"
He pokes Ellie in the ribs on both sides, she squeals and her arms jerk back from Steve's waist to protect her ticklish ribs. Wade uses her distraction to quickly pick her up and sling her over his shoulder.
"CURSES!" Ellie shakes her fist like a foiled cliche villain "MY ONE WEAKNESS!"
Wade plops her down in the chair by her abandoned sketchbook and sits next to her.
"Er...Uh…" Steve is still visibly confused. "Right I called a meeting!"
"A meeting to show off thine belt?" Thor interjects.
Steve shoots Thor a dirty look "No Thor. Not to show off my bel- She's not a belt!"
Ellie gives Thor a high-five.
Thor feels very accomplished at this small gesture.
Thats right, Thor is "hip" with the young ones of Midgard, he is "down with it" as the young people here say.
He can "get jiggy" with his "bad self".
Whatever in Odin's name that means….
Steve is starting to get a headache. "look its not too serious now, but it will take at least a couple of us so I'm asking for volunteers to-"
Deadpool pops up from his seat "I'm not so sure I can go!" He points at his daughter "Secretary write down my itinerary!" Ellie takes up her sketchbook and a couple of markers.
"First and fore-most!" Deadpool waives his finger about "Ellie has a piano lesson this afternoon!"
Ellie pouts but continues to scribble on the notepad. "ugh.. piano" she whispers.
"Peter is working on a paper so of course he will need our help!"
Ellie looks up at her father confused "You can't science…"
"No but I can cook while he sciences!" Wade counters.
"ah." She nods. That makes way more sense.
"Ellie also needs to do her homework!"
Ellie grumbles.
"Also later I plan on breaking into the zoo with my daughter."
Ellie perks up "Can we pet penguins again!?"
"sure thing sweet-pea" Wade pats her on the head.
"yay!"
Deadpool whirls back to his daughter "Now read me back my itinerary secretary!"
Ellie looks down at her sketchbook "I didn't write down the itinerary, I DID draw a picture of Iron man touching Captain America's butt"
She handed her dad the picture of a scribbly Captain America bending down like pin-up girl, butt perky and prominent while Iron-man touches the butt.
Deadpool looked at the picture for a couple of seconds.
"GENIUS!" he yelled "THIS IS THE KIND OF THING I LIKE TO SEE! YOU MISSY ARE GETTING A RAISE! INSPIRED! REVOLUTIONARY"
Wade addressed the rest of the avengers "Everyone follow Ellie's example she knows how its done"
Wade proceeded to use a dagger to pin the drawing to the wall the same way normal people put their kid's drawing on the fridge with magnets.
"Thats not staying here" Tony tried to insist.
Clint's head hit the table he was laughing so hard.
"Ah ha!" Thor Exclaimed "This drawing, Steve is 'getting jiggy' with his 'bad self' is he not?"
"I kind of like it there" Natasha nods approvingly at the drawing "I say we keep it"
Bruce looked thoughtfully at the drawing "I'll admit the kid has a talent for drawing butts…."
"OH FOR THE LOVE OF!" Steve started to yell.
Just then something green and slimey thudded against the window, it snarled as it slid down the glass, leaving green goo in its wake.
"I was trying to tell you about the mutant blobs running amok but no!" Steve threw his hands in the air "You all had to talk about butts!"
"I see no problem with the topic of butts" Natasha deadpanned.
"Just will someone go outside with me to help me deal with this!?" Steve yelled.
In the end the afternoon was spent killing small blobs of goo that had multiplied quickly and now infested the city.
Ellie grabbed one of Tony's vintage Baby Ruth baseball bats and helped. When she tried to return the gooey and scratched memorabilia Tony said she could keep it.
Score!
She also missed her piano lesson.
Double score!
They went home, cleaned off all of the goo off themselves and made an enormous mess in the kitchen trying to bake a cake for an overworked Peter.
They ended up ordering out.
Peter took a break from his work to eat with his family and they told him about their day filled with butts and goo monsters.
