Ok, so I have a massive chip on my shoulder, obviously my DC is the most important person in my life, right, like most mothers out there? 
well DP took our DC his DD to visit MIL. When they arrived, MIL also had DPs 3 nephews ( her grandchildren) there. They all decide to go out, mil pays his Dd, and the other grandchildren into crazy golf! What about DS? To be fair, he is too young for the game but there are other activities that were suitable for his age group.
I am not someone who expects anything from anyone, I just think it would have been decent of her to say, aww here's something for DS to do something while we are doing this!! Only because she must have been feeling flush to treat her other grandchildren? Or am I just over sensitive?