My sister-in-law ruined the gender reveal for my first baby. Am I wrong to be mad?

Question: "My husband and I are about to announce the gender of our first baby. We have had two previous pregnancies that resulted in miscarriages, and our parents really shared in our pain and grieved those loses. We thought it would be nice to let our parents know the gender first, as they have been through so much. My husband’s sister called us a few days ago to find out what we were having, but we explained we weren't going to tell her until after we told our parents. She said that was OK.
We live in a different state than our families, and we told each set of parents that we were sending a package containing the results and explained that we wanted to share it with them first and then we would tell everyone else. Once SIL (sister-in-law) found out about the package, she asked my MIL (mother-in-law) if she could be there when they opened it. MIL said it was OK, but never asked us how we felt about it. I tracked the package, told both our parents when it would arrive, and my husband sent out calendar invites.
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Today when talking to MIL, she mentioned SIL will be there as well. I mentioned to her that we would prefer it to be parents only, and may be awkward as the package contains gifts only for them. MIL told me that I would need to explain to SIL why she can’t be there. I texted SIL and explained that we aren’t trying to exclude her, but we want to share the moment with our parents first. I said we are excited for her to find out too and would give her a call the next day to share the news. SIL lost it! She called MIL and told her that we are excluding her and that we’re not thinking about her at all.
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MIL told me that I needed to tell her that we did actually want her there. I explained the situation to my husband and he called his mom to reiterate what I did to her initially. SIL tried to call me, but my husband insisted he answer instead of me. He explained the same thing to her, but she told us that when she had her baby reveal that she invited everyone and we should do the same. My husband told her that we are doing it our own way. She was still upset with us, said some mean things and hung up. Now my husband and I feel like our gender reveal has been ruined by the drama. So, am I wrong for not wanting her to be there when gender is revealed to our parents?"
Answer: First of all congratulations on your little one! I can imagine it’s been a difficult journey for you, so it’s no surprise you wanted a happy, drama-free gender reveal for your rainbow baby. You are not wrong for wanting to accomplish your gender reveal celebration in a specific way. It’s clear that you and your husband made your plans and communicated them clearly to both your parents. Unfortunately, your sister-in-law took it personally and felt excluded. It seems she’s having a difficult time with boundaries, which is why it’s so important that you and your husband reiterated how you felt and held strong.
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I think it’s best when partners handle having tough conversations with their family of origin, and your husband did a great job of this. This isn't about your sister-in-law, which he reminded her of when she tried to pressure you to conform to her gender reveal standards. Additionally, I think your MIL may be used to letting her daughter get her way, as she clearly went against your wishes by inviting her to the reveal. I also don’t appreciate that she made you make the call to disinvite her, as she should have been the one to correct the issue she created. It sounds like your family is very close and full of love and I don’t want to discredit that, but this drama may have been avoided if MIL didn’t overstep and divert from the plan.
It’s clear this is a very special moment for you and your husband to share with your parents, and a lot of care went into creating a memorable experience. I have the mindset of your gender reveal, your rules (unless you’re at risk for starting a forest fire). Your sister-in-law is seemingly creating a lot of drama by making this about herself. Or at the very least shifting the attention from what’s really important here: the little one you're expecting. Waiting an extra day is nothing in the grand scheme of things. Don’t feel bad for how you wanted to share your happy news, and keep setting those healthy boundaries.
Morgan Absher is an occupational therapist in Los Angeles who hosts the podcast, "Two Hot Takes" where she and her co-hosts dish out advice. She writes a weekly column, sharing her advice with Paste BN's readers. Find her on TikTok @twohottakes and YouTube here. You can reach her by email at Mabsher@gannett.com or you can click here to share your story with her.