Massallah pertaining to family ties

I am a very busy person, as I am working and studying but will welcome anyone in my home, except a particular family, I do not like them, they are extremely materialistic, they slander my father all the time, and I have heard that they do evil things. This particular family wants to stay in my home while I am not here. They did not ask me, They spoke to my father and he happily agreed. This womens son lives here but she will rather come and stay here (I am not such a close relative)
They knew that I am going on holiday, but still asked for the house keys. Is this permissable.