B.G.
Seperation anxiety usually happens around 9 mos or so. My daughter started at 6 mos! The only thing you can do (that I found to be somewhat successful) - is kind of play hide n seek. Get out of his view for a minute, talk to him so he can hear you, and then pop back in and say "see Mommy is right here". Then slowly increase the amount of time you are out of his sight. I felt that leaving my daughter to cry made it much worse but I also learned how to include her in my daily chores without it being a disaster (either the mess or her freaking out).