There is a round clearly artificial pod in the middle of the crater, with a tiny little window set into what could be a door. The pod does not look like any sort of earth design, capsule corp and other major technology companies have a very different style to their machines. It is a Saiyan space pod from the planet Vegeta.

If Gohan approaches he will see a sleeping toddler through the window in the pod. The pod hisses slightly as its outer layers are cooled down by the internal workings of the pod.

Of all the things he had been expecting to see, a boy in a spaceship was not one of them. Gohan waits or it to cool down, an looks for a way to open the hatch. A child this you shouldn’t be on his own, even if he doesn’t know if they’re from earth at all. Son Gohan is not paicularly skilled with earth technology, much less saiyan tech; he doesn’t really get anywhere before it’s cool enough to touch. 

After it cools down enough to touch the pod pops open after Gohan must have pressed the right spot somehow with a hiss of released air. The toddler inside is fully asleep in a little armored suit, and has a monkey tail!.

There is a message that is playing. A male voice is going “Listen son, do whatever it takes to survive got it?.” And then a female voice goes “we’ll see you really soon.”. “Goodbye” says the male voice. “Dont forget us Kakarot!.” The message ends with the female voice.

Perhaps someone more knowledgeable on linguistics would question why aliens spoke the same language as earth, but to Gohan, it seems natural. He doesn’t know what disaster caused these people to send off their son, but it certainly doesn’t sound like they expected to be able to return and pick him up, nor do they seem to have someone here ready to take him in. 

He takes a moment to scribble into the dirt that he’s taken the boy, just in case someone does show up, and then carries the sleeping toddler back to his house. 

The toddler sleeps well all the way back to Gohans house, he was probably put to sleep by the pod for the long voyage not that Gohan would know this.

A few hours after being taken back to Gohans house in the forest the toddler will wake up and start yelling and crying, if Gohan isn’t in the room he will start thrashing and breaking things.

Gohan has no idea how to raise a toddler, but it's far too late to make a run to civilization to get help or a book or supplies that night. Instead, Gohan makes his futon up for the child, and settles in for some sleep himself. He's woken by the yelling, but he knows at least that much of parenting a child; he heads over to Kakarot and attempts to soothe him. 

If Gohan gets close the child at first pushes Gohan away pretty hard, this is an unreasonably strong toddler. This is a strange person and the child wants his mommy and daddy and is a little scared, eventually going from agression to just crying after a while.

This kid pushes hard. A normal person might be injured, even if they were a healthy adult and didn't land badly.

Son Gohan, on the other hand, is a martial arts expert and has the strength to match. He respects Kakarot's desire for some space (he doesn't know much about kids, but that message gets through clearly) but the push doesn't budge him at all. He's calm, reassuring, and attempts to comfort Kakarot once he starts crying. Somehow, without appearing to move a step, he gets some hot tea ready to offer to Kakarot, and some food in case he's hungry; not a lot, though, he thinks he's dealing with a mostly normal toddler, not a Saiyan appetite. Humans aren't supposed to move that fast!

When the pushes dont move the man at all his eyes go a little wide and he stops doing that, Instinctively respecting strength.  After he has gotten the crying out of his system the kid notices the food and makes grabby motions with his hands, prehensile tail even reaching for it.

The old man moving that fast doesnt seem to surprise the boy, having labelled the old man as “strong” in his head so anything like that just makes sense to him.

The food is just some leftovers Son Gohan had, but it is pretty tasty. He seems more surprised than anything at Kakarot’s appetite, but he has no idea how long it’s been since Kakarot last ate, so he’s willing to keep mor coming until Kakarot is willing  done eating or has eaten everything he has.

The child will have kept eating until Gohan has run out of leftovers. A tail and being able to eat more than a toddler his size should be able to, what a mystery.

The child seems a lot friendlier to Gohan now he has had time to cry and had a good meal, grabbing at Gohans fingers and clothes playfully. 

Friendly children. good. Gohan knows how to deal with that. Kakarot doesn't seem old enough to understand the full situation, but that's no reason not to explain it to him, and help him understand as best he can. He takes in kakarot, as though he's his own son, with all the love - and all the false starts - that implies. Luckily, Gohan is very strong and quite durable, which obviates many possible concerns. 

One night, however, it's the full moon...

Kakarots eyes go wide when he sees the full moon, and they glint red, and he starts screaming at the top of his lungs as his muscles bulge and fur appears over his body as he starts growing.

He is turning into a beast on the full moon! a mighty Oozaru!.

Gohan is out of the house at the time, but he can hear the yell, and as he rushes back, he quickly becomes able to see it as well. He's not sure where this monster came from, btu juidging by how easily it rips out trees and how fast it's moving without seeming to be trying, not to mention it's enormous size, it's at least somewhere in his league. He'll have to be careful, especially since he has to get it's attention before it gets to the house and therefore Kakarot.

"Ka-me-ha-me..."

And the beam of chi from Gohans hands smacks into the enraged Oozaru, and it turns towards Gohan with a snarl on its face, crashing through the trees and away from the house towards him. Roaring and flinging trees.

He dances back out of reach, dodging the trees. When it takes a swing at him, he steps inside its range and slams it in the chest. 

“Raaaaooowwrrrr!” The great monkey roars in frustration and stumbles back, the hit strong enough to push it’s huge weight back. Lashing out with its tail at Gohan.

The blind rage makes it clumsy and stupid. The stance is full of openings, the movements slow and it only has it’s great strength and size going for it.

It's kind of hard to hurt something this big, but it is off balance, and it's giving him a target. He grabs the tail, and attempts to pull it over on its back.

As soon as Gohans hands are around the tail the beast whimpers and slumps and looks as if it has had all the strength taken out of it, being easy to pull it over onto its back as long as the tail is being held.

That's certainly odd. He puts it on it's back, then releases the tail and steps back, seeing if it's going to keep attacking.

As soon as Gohan releases the beasts tail it gets back up and roars, swinging wildly in the direction of Gohan, keeping its tail mostly behind it now.

It's not any more skilled than it was before. He sweeps out it's legs from under it, this time.  It's kind of hard to pin, but he can keep this up all night.

If he does not go for the tail again he might have to! The mighty mokney beast does not seem to tire very much even as it turns into the early hours of the morning. Even when pinned it struggles in a blind rage trying to lash out at Gohan.

It takes him over an hour to get them there, but Gohan isn't as young as he used to be and there's no real way to safely knock someone out. Once he grabs the tail, he attempts to communicate; he doesn't expect a successful communication, but there are all kinds of of people in this world.

Just growls and whimpers coming from the Oozaru, too weak to retaliate but clearly still has animosity to Gohan, eventually it just lays there slumped saving its strength.

Eventually the moon goes down across the horizon and the Beast starts to shrink into a familiar little boy with a tail.