Mom In Law

Just feeling annoyed but not sure where to share... Mom in law asked me n my 2 boys 4 yrs old and 3 mths old to come over to my bro inlaw house. No occasion. Just that she is going there so she asked us to come over. I agreed coz i thought its in the afternoon. Turns our she arrived there at 7plus and expect me to come over soon after. ? My husb is working though so its just us 3. My baby needs to sleep by 10 so that i can REST. Im just surprised and upset that she was being self centered and not thinking of my situation. If she really wants to meet my baby why not come over to my place then? ?