In laws upset

My in-law are upset that my brother in law and his girlfriend moved in with us. I live in a 3 bed 2 bath home with my husband and mom. My bil and his girlfriend recently graduated and he has started working full time. My bil was expected to pay most of the rent because his girlfriend was going to move in. My father in law was hurt at work a while back and hasn’t been working so my mother in law got a job. They wanted my bil to take majority of them rent because his girlfriend was going to move in. My husband told his brother he could stay with us and he would only be paying $400. It’s a better deal for them but it leaves my in laws struggling. They’re upset they’ve moved in with us and we have 3/5 working adults living here and they have 1/2 working adults plus 2 kids. I know it seems super unfair to my in laws but my brother in law and his gf just graduated HS and she’s going to school full time. I don’t know what to do. My husband is sad that he mad his parents mad but we just wanted to help them out. I’m sorry if some of this doesn’t make sense. I tried telling it the best I could.

What should we do? Should we tell them to go live with my in laws?