Ok.

My mother-in law came here alone when I had my baby. She got a B2 visa valid for 6 months with multiple entries. She got 6 month I94 last time but stayed here for only 5 months. So I think she has great credit for that.

This time, my father-in-law is retired so he came with her. Their B2 visas have only one entry, and valid for only 3 months. But fortunately, their I94 is still valid for 6 months.

They got their visas at the end of May.Quite easy for them to get the visas.