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Helen was in a mad dash out of the door. Bob was away on a mission, Dash was at summer camp, and Violet was on a date with Tony. She had no one else to turn to but she needed someone to help her out right now. She couldn’t take Jack-Jack with her but she couldn’t very well leave a six month old baby on his own alone at home.
“Thank you so much, Bruce. You’re an absolute life saver,” the stressed out mother applauded.
Bruce let out a light chuckle. “Think nothing of it, Helen. Now go, go! Take care of your business! For as terrifying as the Abomination or the Underminer might be, the IRS is an unstoppable force that no hero or villain can ever defeat.”
“Oh when you’re right, you’re right. Take care, Bruce,” she handed the baby to the professor and kissed his head. “Bye Jack-Jack! I’ll see you in a few hours! Mommy loves you so much! Please be good to Dr. Banner, okay baby?”
And with that, Bruce’s former colleague was out the door.
Bruce smiled down at the little guy now occupying his arms. “So you’re Jack-Jack? It’s good to meet you little guy.”
As if the child could mystically detect his mother was away despite not yet having object permanence, Jack-Jack began to act mischievously… By immediately bursting into flames.
“OH MY GOD!” Bruce yelped, running straight for the kitchen sink. In the back of his mind, Bruce knew he could logically assume this was just Jack-Jack’s powers activating but he had no reason to know that for sure and that kind of logical thinking took a backseat to the material reality OF A BABY BEING ON FIRE!
Bruce, ignoring the horrific pain of the flames surrounding the little guy burning his hands, set the baby in the sink and started running the water… Only for the fire to immediately dissipate.
“Oh, it was his powers…” Bruce chuckled. He glanced down at his hands as they steadily started to green as they healed on their own before returning to his normal skin tone. “Not here Big Guy, not here,” he huffed, letting out a sigh of relief..
Bruce and the Big Guy had long since settled their issues with each other, but there were still some places that were better suited to Dr. Banner and not so much the Big Guy.
“Okay little guy, let’s not do that again okay?” Bruce requested. “No more fire. Fire hurts people! Okay?”
Jack-Jack nodded and gave Bruce a thumbs up.
Bruce smiled. “You’re a smart little guy, aren’t you?”
Jack-Jack grinned widely and held out his arms.
“Uppies?” Bruce asked, his voice light with amusement.
The baby giggled and began to float up out of the sink.
“Oh WOAH!” Bruce laughed, grabbing the little stinker out of the air. “Okay, someone really won the genetic lottery.”
Jack-Jack looked at him confused.
Bruce looked back at the child, also confused. Did he actually understand him? “So on the off chance you actually know what I’m saying, genetics is basically what makes people, people. A lottery is sort of a contest where people are all competing to get a big prize.”
Jack-Jack looked at Bruce with wide awestruck eyes.
Bruce shook his head, still smiling at the little guy. “Well, you’re not floating away from me anymore, are you gonna do anything else crazy?”
Jack-Jack giggled and turned to steel.
Bruce wasn’t prepared for the sudden change in the baby’s weight and dropped him on his foot, making Bruce cry out in pain and while Jack-Jack continued giggling as he crawled off of Bruce’s foot.
Bruce collapsed onto the floor, gripping his foot in tremendous agony. He glanced at the baby crawling across the floor. Still none the worse for wear. “I dropped you. I was worried you’d be hurt. I’m glad you’re not.”
Jack-Jack giggled again, gently tapping Bruce’s foot, healing it quicker than even Bruce’s healing factor could.
The professor let out a heavy sigh of relief as the pain quickly faded. “Thank you. Thank you very much, Jack-Jack.”
Jack-Jack kept giggling.
Bruce snorted. “You really like to laugh don’t you?”
Jack-Jack clapped his hands and continued giggling.
Bruce smirked. “Well, you might be a handful, but at least you’re always happy. That’s a good thing,” the scientist steadily got up off the floor and picked up the baby. “So what do you wanna do now? Watch some TV? Play with your toys? Take a nap? Have some lunch?”
Jack-Jack’s eyes began to glow a bluish-green light and began projecting laser beams that burned into the ceiling of the house.
“Or maybe you’d like to display a new super power…” Bruce sighed. “Helen, Bob, how do you handle this little guy?”
The laser eyes quickly stopped, but the chaos didn’t as Jack-Jack started crying.
Bruce tried to start rocking the little guy to calm him down but the baby wouldn’t stop crying.
“What did I do wrong? Why are you so upset?”
The baby didn’t answer verbally but instead responded by transforming into a little gargoyle baby that quickly began hitting Bruce and pulling at his hair.
For whatever reason, the baby was angry now, and now Bruce was starting to get angry too.
“Please stop!” Bruce hissed, trying to keep the little monster at arm’s length to no effect. The Big Guy was banging at the door in Bruce’s mind now. “No Hulk, this isn’t the place! This isn’t the time!”
Finally Jack-Jack struck Bruce a bit too hard and Bruce’s brown eyes turned radioactive green.
Bruce set the demon baby on the couch as quickly as he safely could as his skeleton began to expand and his skin began to stretch, a horrifying noise filling the room as his body began to change. Dr. Banner was leaving the room and the Big Guy was coming in to fill for the rest of the afternoon.
Demon Jack-Jack began to giggle again, clapping his hands even more enthusiastically as the big green machine took his place.
The Hulk let out a powerful roar that would’ve likely shattered the windows of any other home. Luckily, Bob and Helen thought ahead after their home was destroyed during the whole affair with Syndrome.
The Hulk stared down at the baby, his furious expression not phasing the little one who seemed to be incredibly excited to see his babysitter change like he did.
Jack-Jack crawled up the Hulk’s leg and settled into the enormous man’s arms, letting out a yawn as he closed his eyes and nodded off.
The Hulk’s rageful expression quickly softened.
“Awww baby,” the monster’s deep voice cooed before moving into the living room and taking a seat on the couch.
Helen returned an hour later to see her baby in his human form curled up on Dr. Banner’s bare chest, his shirt, socks, shoes, and the calves of his pants and Jack-Jack's onesie all torn to ribbons on the kitchen floor. Judging by all of that, the scorch marks in the sink, the dent in the kitchen floor, and the line of burn marks across the ceiling, two had obviously had an interesting afternoon but had clearly cooled off by now.
Helen reached out with her stretchy arms to take the sleeping baby from Bruce’s arms and gently set him in his crib. She then stretched her arms further into the house and retrieved a spare blanket from the closet between her and Bob’s rooms and the kids’ rooms. Finally, she moved into the living room properly and draped it over her guest.
“Thanks Bruce,” she whispered, kissing the gamma hero’s cheek.