So frustrated at my sister in law

Marykate • mom of 2 handsome redhead boys ♡♡
So my sister in law lives with us, and today I found out she gave my son chocolate. He is not even 2 months yet! Like what the heck was she thinking?! I told her never do that again. Now I feel like I can't trust her with my son if I'm not around. How do I handle this situation?