What would you do if this were you?

I have a friend, well we have been friends for like 20 years. We used to be real close like best friends. We are still kinda close I guess but we don't talk very often. Anyway, she called about a week ago and said that her sister which I have only met maybe 3 times needed a babysitter cause their great gramma died. I felt bad cause I did know the great gramma. See her sister,step-sister, lived in California for most of our friendship so that's why I never seen her much. So I was like okay, I felt bad cause the sis was a pall bearer. The baby is 1. We had a lot of fun with her. My youngest is 5 now so it was fun having her around. Anyhow, my friend and her sis came an picked up the baby 5 hours later and I got offered NOTHING for babysitting. I can see my friend cause we would do anything for each other but I barely know her sister and never seen the baby before and I played with that baby non stop for 5 hours and couldn't do any of my chores at home. She is a single mom and I would not have taken much from her but she should have offered but now I feel kinda weird about my friend cause she is the one that called and asked me to do it. So shouldn't she have been the one to say, hay you gonna give her a few dollars for watching your baby? Do I just get used again?