Hellp needed

Mother has two bio kids, a son that is 13 and an aspiring track star daughter that is 9 and that is in competitive gymnastics. The father has a son 10 who is defiant towards female authority figures and peers (including step siblings). He constantly argues and has been aggressive with step siblings. His mother left the family when he was 4 and he hasn't seen her since. The married couple has been married for 3 years.