I also lock my doors, due to the area I live in and my licensing recommendation. Parents can come if breastfeeding but otherwise it's not encouraged...but parents don't really ask to do that either. As long as they are not left alone with the kids I don't see why they would need a CRC. My LIcensing officier had said my out of town company can visit with me and my dck's when here without a CRC so obviously my dc parents could.