Dear Abby: My husbands parents always choose his twin will they ignore our children, too?

DEAR ABBY: My husband has a twin brother and a younger brother.After I met his family, it became clear that his parents openly favor his twin, “Kaden.” Based on childhood stories my husband and other family members told me, his parents have spent most of their time, energy and money on Kaden.
Previously, it made sense.Kaden had health problems as a child and required extra care.
But now, although he’s a healthy adult in his mid-30s, the situation hasn’t changed. Some examples: During his speech at our wedding, my father-in-law asked the room to toast to Kaden’s various achievements instead of toasting my husband and me! My in-laws cancel visits to us because Kaden decided to visit them at exactly the same time.They have planned their vacations based on places Kaden thinks they should visit.
Speaking to them on the phone is infuriating since most of the conversation is about what’s going on with Kaden. I don’t speak to my husband about it often because he gets angry when I bring it up, and their younger brother just shrugs it off as how things have always been.Kaden and his spouse are now trying to have a baby, and my husband is asking that we start trying, too. Abby, I’m hesitant.
I believe it’s important kids grow up with the love and support of grandparents.But based on their behavior for the last 30 years, I’m afraid that if both of us have children, his parents will continue this favoritism toward Kaden’s family. I am anxious about his parents forgetting our kids’ birthdays or not wanting to visit them.
I’m loath to put my children into that situation and am considering refusing my husband’s request, whatever it may mean for our relationship.Am I being unreasonable? — UNFAVORITE IN THE WESTDEAR UNFAVORITE: Because of the degree of dysfunction on your husband’s side of the family, it might be helpful to talk this through during some sessions with a marriage and family therapist.
You didn’t mention in your letter whether...