constant squabbling between him and his sister... When he realized his little sister could pump herself on the swing and he still couldn't, he attacked her for it rather than practicing himself, screaming the playground down.
Possibly a good topic for the therapist or counselor you were referred to? It is possible that if the relationship were to improve the siblings could play together... some day bike/run/walk/kayak/scooter/practice soccer dribbling together?
In reading this about DH
I wish my husband would take him biking more often, but he moans he doesn't have time either (and says he was just as useless at sports and grew up fine regardless, conveniently forgetting that he must have been one of the unhappiest middle schoolers around. So, no buy in there, which is one of the problems,)...
Again, husband hates having to take the kids places, need more buy in there because I can't do it all alone.
One of the problems with the martial arts class he did up to now was that whenever I didn't drive him, husband wouldn't either
and this about DS
he is at a point where he needs to actually try hard, get out of his comfort zone. He won't. He rather told the instructor he didn't want to be there anyway.
Is it possible that DS has learned non-participation from DH? Possibly an aspect of the family dynamic to discuss with the counselor or therapist you were recommended to?