<prompt> Human: My wife and I just allowed mysister in law to move in with us while she goes to college so that she doenst have to worry about housing and food. We arent charging her for rent, utilities, shared meals etc. Were also taking care of things like glasses for her, cell phone bill and all car repairs.She hasnt been filing independently and her mother my mother in law has agreed to allow us to claim her as a dependent on our taxes for this year.What I was wondering is the legality of this. While we arent her parents, and while shes legally an adult she is technically dependent on us. Are we able to claim her as a dependent?Thanks!  <response>: The IRS has pretty clear rules about this. Take the test they have provided online. 