Me, DH and our two DC (3 and 1) live about an hour from MIL. We visit about once a month as it's hard for us with work and juggling the kids etc.
We have an open invitation for MIL to come to us and I will message every couple of weeks asking when she is free and usually she says she will get back to me but doesn't. She was saying to DH she hadn't seen the DC of late so I messaged her asking when she was free to come and visit (we did visit her two weeks ago). She replied:
"I can come next Saturday for your lasagne?"
I explained we are at a birthday party that day but could do any evening (I mean after 4pm so she would still see the kids) and she said she doesn't have any free. She doesn't have a job by the way.
I thought it was a bit much to specify one day she can come between now and the end of the month and to also specify what she wants me to cook which I thought was cheeky. However I do find quite a few things a bit annoying and maybe I'm being a bit harsh.