...what's the most irresponsible thing they've done?

I was just sharing in another thread that my mom was giving LO a bath the other day while I cleaned up his toys from around the house. She walked away and left him in the tub alone while she answered her phone! I hear her with the phone and rush to the bathroom to see LO alone and standing up on the side of the tub, I was furious and so glad I was there...and that's exactly why I never leave him alone with her!