I don't know 45, if I saw an 8 year old kid beside a 4 year old kid. Even if the 4 year old was about the same size as the 8 year old. I'd assume the 8 year old would beat the 4 year old up. But when the 4 year old turns 16 and he's now bigger then the 20 year old. That 16 year old might considering he's growing much faster would beat the snot out of the 20 year old. But it's funny how hive guys like to think the 8 year is such a big strong kid beating up a 4 year old..even if the 4 year old is growing faster.