We have a big family at home, due to my mother taking foster children. However when she (my mother) or my sister go on holiday or my sister to a sleepover the dog gets very "protective" and even kind of aggressive. She will guard for example, my sister’s bag.
The problem is signifact when we go to bed: She has to go to her (kennel / cage?) where she sleeps everyday. However without them present she doesn't obey at that point and trying to pick her up has a high chance of getting bitten. Signs are that her ears go flat en her tail is between her legs.
The dog is part Jack Russel and part something else.
When everybody is home, she is the sweetest dog there is.