Anonymous wrote:OP, here's the thing. Your daughter is FOUR. The chances she will remember any of this are basically NIL.
So, what your daughter will remember from this year forward is either her Auntie Sue and Uncle John who love her and who have a cute little baby who she adores and can't wait to see a few times a year, or that aunt and uncle who she never sees and a cousin who she barely knows.
You don't have to be best buddies with your SIL to have a strong, warm relationship between your families.
OP here. Thank you for your comments. The comments about how great the cousin relationship could be in the future if we decide to forgive and forget really resonated with me. Although I am annoyed and hurt by my SIL and BIL's actions, I feel like the more important issue is that my daughter get to know her only cousin and that they have a good relationship. Both DH and I have very small and non-local families, and they are our closest kin in terms of distance (everyone else lives much farther away). And the fact that their baby will be our daughter's only cousin. So I feel like the cousin relationship is the most important issue here, despite how upset DH and I feel about the way we were treated. I want my daughter to feel like she has a relationship with extended family, and a strong bond with extended family, and I think I can put aside how we were treated in order to nurture that bond.
I think back to my own extended family, and how one of my uncles was shunned from the family for over 40 years for some petty reason, and I never got to know his three kids (my first cousins) until the last few years when he decided to let the past stay in the past and reconnect with the family. It would have been wonderful to know these cousins when I was growing up.
Also, just wanted to clarify that SIL and BIL never shared any details of their infertility struggles with us. We learned what they were going through only through DH's mother. So we never really felt comfortable bringing anything up with them about their infertility procedures, treatments, etc. as MIL wasn't even supposed to share those things with us (but she is a blabbermouth). They didn't even share that much of what they went through with her, they wanted to keep it to themselves, I guess. Similarly, we have not shared anything with them (or MIL) about our secondary infertility issues. They don't even know that we have infertility, or that we've been TTC for a year now with no pregnancy. They also don't know that we got pregnant with our daughter after just one month of trying (when we announced our pregnancy to the family they asked specifically about "how long" it took, but we just brushed that off and did not tell them, out of respect for what they were going through.
Thank you for all your comments, this thread has been great for thinking about the issue in different ways.