How to handle in-laws..?

We don't know how to handle this.. my in-laws call us multiple times a day just in check in. We've started not answering the phone because we want space. Then today my mother in law called crying that she never hears from us. We're not trying to hurt their feelings, but we're adults and they still treat my husband like he's a child.

We don't mind talking to them. But multiple calls and texts every day is sending us over the edge. Is there a good way to handle this without upsetting them too much..?