I just cut Curly's hair for the first time last month, so she was 5 months.
I agree with the poster who said to learn about hypo glycemia. This is a HUGE one for Yorkies. It happened to Curly a couple times when she was young and had I not walked in when I did and found her all balled up, she would have died. Then I may have followed her
Take care of your new baby, he's very young and needs you big time!