I don't even know.
All I can think of he has major PTSD. I hope he helped people as a medic, but take out his aggression or whatever on his baby is beyond the pale. Go to a boxing ring a therapist, but he just violated and lost one of the most precious gifts he was ever given.
They both need our prayers, as does the mother.
PTSD will not make a person harm a child. I know you are trying to understand this evil, but it’s not PTSD. It’s something else.