Other sims in the household keeps taggling along when traveling

Whenever I send one sim or two to another lot, another sim in my household tags along uninvited. This happened when I sent my sim's parent's on a date, in which the daughter came along uninvitedly and I was unable to send her back home because it was an event. This also happened again when I sent my teen sim to hang out with her friend in which the dog randomly tagged along. It's very frustrating, especially when they do this during dates or other hangout events in which the send home option is greyed!!!