A man on Reddit says his sister accused him of trying to "steal" her thunder after he got engaged during her wedding ceremony.

The man detailed that he and his partner of 10 years had previously talked about marriage, and had done everything except "gotten the special piece of paper and had a party with family."

Despite the two having gone to "plenty of lovely weddings" together, his sister's wedding night felt like the right time to pop the question.

"My sister’s wedding was this past weekend, and it brought up a lot of unexpected feelings. My partner and I have never been particularly bothered with the idea of a big wedding (and we’re still planning on keeping things small) but there was something special about that night," he wrote via Reddit. "In a private moment just between us two, I asked him to marry me and he accepted. There was no big show, no getting down on one knee, just an intimate moment between the two of us during the reception."

The couple didn't tell anyone their happy news until days later during a family gathering.

"My partner and I said how beautiful her wedding was and how moved we were and told the story of that special moment that she helped facilitate, even if it wasn’t intended," he wrote, noting his sister was furious when he told her.

"Instead of happiness, we were met with anger. She argued that it was disrespectful and undermined her event, that we were trying to 'steal her thunder,'" he continued. "I wasn’t even planning on sharing this story with anyone but mine and my husband’s immediate families and friends. I also thought it was harmless because we didn’t call attention to ourselves."

The newly engaged man's post was met with mixed reactions. Some agreed he technically didn't do anything wrong, but felt he probably should have waited.

"If it was a quiet moment with just you two, no one else noticed, you didn't cause a scene, no one jumped on a table and announced it to everyone present, I think you're OK. As long as in the future you don't make a big deal of it or anything, and don't advertise that you got engaged at your sister's wedding. And definitely don't bring up your engagement anytime someone talks about sister's wedding," one person wrote.

"The rule about not getting engaged at a wedding is 'don't steal the spotlight while someone else is getting married or celebrating at the reception.' It never meant two people can't decide, privately, to get engaged at a wedding and tell people later. I'd be so touched if my wedding inspired this for someone else. Congratulations and I'm sorry your sister doesn't see it the same way," another commented.

"YTA [your the a--hole] for the timing when sharing that story with your family. Why did you have to do it at an event where you were seeing your sister off for her honeymoon? You could easily have delayed the news until after the honeymoon and left out the part about the proposal happening at the actual wedding, and everything would have been fine," someone else weighed in.

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