There is so much information to give. My son Dylan is 4 years old. He is in preschool but not doing well with any of it. He constantly is put in time out for screaming, yelling no, pushing, biting and the list goes on and on. I try so hard to keep structure in the home but I am at my wits end. He is on respirdal (mood stabilizer) and I am still exhausted. If he is around just me (no dad or other family) he is well behaved. Dad walks in the door and **** literally hits the fan. He is so defiant. What can or should I do???