my 7 year old boy said he doesn't want to live with us

Ok. I don't want judgement. I'm trying to vent and get some advice. It happened that my boy was playing with his cousins but by the end a family member bring him home. As he arrieved he was crying and said that everyone get the chance to have fun, but not him. Because his other cousins stayed at grandma house. So he told me that he doesn't want to be home. Wich make me feel so sad 😭. He said he prefer to live at grandma's house and that he doesn't like us. I told him that he can have fun at Granma's house for some days but then he will prefer to be with mom, dad and siblings but he kept saying that he wants to leave.