I have recently crossed business with pleasure and have been bitten in the butt. I began receiving texts and invitations from the parents as if we were friends, and I am totally uncomfortable with this (I also started getting flirty texts from the husband, and it almost turned into a huge deal). The parents have also been sending dcb over on the weekends and it now feels like I am working seven days a week.
I strongly discourage giving daycare parents any kind of idea that you're friends. So much can go wrong.