So which boy do you want to gain? Here are you're choices:
Richard James (or RJ)
6 years old.
Short brown hair, caucasian, slim.
Likes to climb trees, play baseball, and watching TV.
His parents think he's underweight, so they try to get him to eat a lot.
Brian
8 years old.
Semi-short dark-blonde hair, caucasian, pudgy belly.
Likes playing video games, doing stuff on the computer, and wants to be an astronaut.
His mom works at a local bakery who often brings cakes and such home. He also has a 13 year old brother, Derek, who he likes to compete with.
Benji
4 years old.
Short ginger hair, caucasian with freckles, thin.
Likes his blanket, cookies, chocolate, and other sweets.
His parents are divorced and he lives with his mother who's working most of the day.
Alex
7 years old.
Short black hair, caucasian, overweight.
Likes food, and watching TV. He's also very lazy.
His parents have a higher income, so they can afford better things, but they aren't filthy rich.