When someone in your family needs a place to stay, and you decide to offer them your own home, just know that it will probably be a long while before you will be able to see them out. Never have I ever heard of someone saying "It will only be a couple of weeks" and have them actually come through with that statement. Before you know it, they ask for another week, and then another, and soon enough, they have been living in your basement rent-free for the past six months, without any intention of leaving.
That is not to say that you shouldn't help your family when they are struggling, just know what you are getting yourself into, and maybe prepare for that in advance. For instance, maybe decide together that if they end up staying with you for longer than two or three months, they must start contributing financially to the household. That way, you are not losing so much by helping them, and it might even encourage them to get back on their feet faster.