I have a black silkie named gronkowski (she's a girl but I didn't know that when I named her lol) that does the same. One time I didn't see her and she got left outside. Good thing I have a secure run. I felt so bad for her. Now I have a flashlight In hand lolSunset. Except for Hortense. She likes her 'me time' and stays out just a little later until it's actually dark.