My sister-in-law (who lives away) occasionally comes to visit my wife with her young daughter. She always comes without her husband who does not want to visit. We have 2 similar aged kids so it's an opportunity for the kids to get together and play.
Every now and then my wife and sister-in-law will want to go for the day and leave me on my own with the 3 kids. Obviously I have no problem looking after my own kids but I feel I am being taken advantage of when I have to look after my sister-in-law's child as her husband refuses to come down and she will not even ask him to look after their own child while she is down visiting. I mentioned this to my wife and she ending up flipping it around to make me feel like I was being unreasonable.
Am I being unreasonable or do I have a point?