My 3 year old is driving me insane

Kari

Help! I have a 3 year old almost 4 and LO will be 6 weeks on Monday. My oldest had been doing so great with the new baby. I’ve included him, made sure to have time with him, let him help us, and he started acting like a demon child this week. It’s breaking my heart because he is such a sweet child and was always my cuddle buddy. What do I do? He’s being so mean to us. Talking back, not eating, hitting, doing things just out of spite. Taking away things, time out, and spankings aren’t helping at all.