My Ds 3 has had motor probs, he eventually walked at 2.5, he still has weak limbs & trunk area but is getting stronger. We now find a whole different set of probs with his behaviour. We thought it was a defense mech with not being walking but he's a nightmare, he's no self control, he constantly attack his sister in unprovoked attacks, he throws whatever he's holding in any direction getting to the point we can't take toys out as there's a chance he might throw them at other people, he just laughs when I try naughty corners & steps he laughs at me.Someone who knows him quite well suggested adhd, is he to young to be dianosed with this?