I am currently watching my friend's daughter during play date with my son for a couple hours a few times a week. I offered to do it for free since they could not find any arrangement. I figured a couple hours of play date will be good for both kids. I offered that she brings her kid over but she insisted that us coming to them is more comfortable for her daughter bc her husband works from home. So its' been a few weeks now. More often than not and especially lately her daughter is whiny and doesn't want to come out when we come over. Then she goes after my son and takes away any toys that he picks up. If he tries to do the same, she stars crying and gets upset. Something is telling me she is already upset before we come not because of us coming. This whole situation with moodiness and guarding her toys makes me uncomfortable. Also I want my son to enjoy play date. Otherwise, what's the point for me to bring him over? Are the kids spending too much time together and need a break? My friend will be off work during spring holidays and I am not sure if I want to continue regular play dates on their territory anymore. How can I tell this?