MIL favoring bio gkids over my son
I have a MIL who favors her bio grandchildren over my son. My husband has 2 from a previous marriage and my MIL stays in contact with their bio mom so they visit her often because my MIL calls her for the kids. My son was adopted at the beginning of the year and my MIL told my 8 yr old that he really was her grandson now after her son and I had been married for almost a year. Even after the adoption the favoritism has continued.
My husband and I had a wedding ceremony and reception this year because we had gotten married at the court house. My MIL posted pictures stating welcome officially to the family. Now that it is summer my step children will be going to my MIL more due to arrangements she made with bio mom. Step kids aren't trying to be mean (most of the time) but my son is feeling extremely hurt and left out. What do I do?!