Blending families is rarely easy. Two pre-existing family units coming together as something all-together new is a task that requires mindfulness, good communication, and even better luck. Like, what happens if you find someone you love but your children and their children just don’t feel the same? Or, worse, what if they despise each other? Such was the case for one Redditor’s family, and now the wife’s sibling is asking “Am I The Assh*le” (AITA) if she wasn’t being forceful enough in their warnings.

“AITA for telling my sister people did express concerns about her son and stepson before she got married and she didn’t listen?”

Reddit user u/CryptographerAny6604 went on to explain that their sister had been married to her current husband for five years and the two have a child together. But each spouse entered the marriage with a son and all five people live under the same roof.

“The boys knew each other since kindergarten and they never got along,” the poster writes. In fact, the two were so contentious that the school worked with the boys and their parents to create a “buddy” plan to help them get along… which failed.

“This dynamic did not let up,” u/CryptographerAny6604 explained. “The two of them do not like each other, I personally do believe they truly hate each other.”

But while this experiment failed to forge a bond between the two boys, it did succeed in bringing the poster’s sister and the other boy’s father together.

The family was leery of this romantic entanglement.

“Many of us spoke to my sister about what a bad idea it seemed to be because the boys were not capable of getting along,” the OP wrote. “She told us they’ll have to once they’re family and it’ll do them some good. … she told me she loved her husband (then fiancé) too much to end things or hold off on marriage. … She didn’t like when our dad took her aside before the wedding and warned her it would end badly because of the boys.”

All this finally appears to have come to a head recently, when the OP’s nephew lost a friend to a long illness.

“My sister and her husband wanted all four of them to attend the funeral … [but] Her stepson didn’t want to go, said he didn’t want to support my nephew and he didn’t care. He thought it was funny as hell how upset my nephew was. [He] said he hated the dead kid too.”

And, apparently, other people knew about the stepson’s animosity as well, including, it seems, the dead boy’s parents.

“While at the funeral my sister and her husband were sympathizing with the boys parents and expressed that both nephew and step-nephew said kind things about their son,” u/CryptographerAny6604 continued. “They told my sister and her husband there was no way step-nephew said kind things about their son and he shouldn’t have been there.”

This realization that everyone was intimately aware of the “bad blood” between her son and stepson apparently “humiliated” the sister, who lashed out at her sibling and not doing enough to “warn” her.

Perhaps needless to say, the overwhelming consensus among commenters was “NTA” or “Not The Assh*le.”

Redditor u/Comfortable-Sea-2454 encouraged the OP to remind their sister of the many conversations they listed, all of which happened before the wedding. “NTA,” they ruled. “You tried … your sister and her husband are flaming AHs though.”

“Your sister knows she’s in the wrong, but she’d rather blame other people for her selfish choices,” surmised u/buttercupgrump. “She cared more about getting married than well-being of either boy. What more did she want you to do? Tie her up until she listened? She’d already made it clear that what she wanted was all that mattered. Shame on her. Let her be embarrassed. It’s the least she deserves for ignoring everyone’s warnings.”

Many were taken aback that the embarrassment appeared to be a bigger concern for the OP’s sister than the boys actual relationship. Many more were aghast at the step-nephew’s callousness toward the death of a classmate, especially to the point where even the boy’s parents were aware of it.

Fortunately for both the boys, however, u/CryptographerAny6604 told one commenter that they suspected once their nephew turns 18 there’s a good chance he’ll choose to live either with his grandparents or with them. Hopefully distance will give these two young men the time and space they need to heal.