My MIL told me when we got married that she planned to come stay with us for 6 months to a year when we had our baby.
I tell you what, that was the best form of birth control ever! We never got around to having children.
I mentioned to my mother what MIL had said, and my mom said "I raised my kids, Don't be expecting me to take care of yours." Well, ok then. Thanks. I hadn't even asked her and wasn't even pregnant.
Best thing is to just talk to them, ask them what they want. If you do go stay with them for a bit, if it starts to be uncomfortable you know it's time to go home.