Asking Eric: Friends want to stay with my parents, even when I’m not there

Dear Eric: Lately some of my friends who have joined me on these trips have now become buddies with my mom and are asking her if they can stay up there without me. Now the first time this happened, the friend called me and asked if I was OK with him asking, but the second time it was a different friend wanting to stay there with his girlfriend and he never asked me.