Need advice regarding jealous grandparents.
My son (age 11) has three sets of grandparents (my husband's parents divorced and both remarried). Set A (MIL and step-FIL) lives about 60 miles from us and sees our son (for days at a time) mainly around the holidays and during the summer when we go on 1-2 week driving trips with them (they are wonderful and have no problem with the fact that they don't see their grandson more often).
Set B (my parents) live about 40 miles from us and see our son (for days at a time and also short visits) around the holidays and at other times as needed for babysitting and just for visits. They are both retired.
Set C (FIL and step-MIL) lives about 15 minutes from us and sees our son for short visits at a time with an occasional weekend stay. They live 5 minutes from our son's school so they also pick him up every now and then. They both work full-time and are constantly going on business trips or some sort of dinner function so they really don't have time for days-at-a-time stayovers.
The problem is that Set B and Set C for some reason believe that the other set has a monopoly over our son, when in fact neither does. This past weekend I had planned to go to my parents house with my son to help with a garage sale. We were going to go to their house on Friday night and spend the night and then stay the day on Saturday.
My FIL called during the week to see if our son could attend an activity with him on the same weekend. I told him that I had already planned to take him with me to my parents'. Well he said ok and hung up. He called back on our other line to talk with my husband and basically had a fit about the situation. He started asking if we were mad at him and why my parents always seem to get to see his grandson more than him.
Well, that same night I got a call from my mom to let me know that the garage sale was canceled. She was still expecting me to come to their house and spend the night. Well I told her that I was going to come down on Friday without my son but couldn't spend the night because FIL had requested to spend time him. Well she got mad and said well whatever FIL says goes and they always see him.
So anyway, on the same night I had a fight not only with my FIL, but also with my mom because they both think that the other sees grandson the most and they are jealous of the other set. Well I still went to my parents and my son spent time with my FIL and everything worked out ok.
That's the story in a nutshell. This situation has been going on pretty much since our son was born but seems to have really heated up in the last few years. What can I do to convince these grandparents that there is no reason to be jealous of each other.
Any advice or comments would be appreciated.
Also, one last question? When you visit your parents house without the grandchildren do they give you the cold shoulder? If so, how do you deal with it?