One 19-year-old college student is setting a Halloween-related boundary — and her family isn’t pleased.

In a recent “Am I the A–—-” post on Reddit, the woman shared that her older sister often expects last-minute childcare help. 

“For context, I live at home while going to college part-time and working,” she wrote. “My older sister, ‘Emily’ (26F), has a 6-year-old daughter, ‘Lily.’ I love Lily, she’s great, but Emily has a habit of dumping her on me last-minute whenever she wants a break.” 

“This has been happening for years now,” she wrote, adding that “no one in the family really questions it because, you know, ‘family helps family.’ ”

And Halloween has proved to be no exception.

“So, a few days ago, Emily told me she couldn’t take Lily trick-or-treating this year because she and her boyfriend were going to some adult Halloween party,” she wrote.

“She just assumed I’d do it. I had already made plans with my friends to go out to a haunted house and watch horror movies, something we’ve been planning for week,” the woman added. “I told her no, that she should either take her daughter or figure something else out because I wasn’t available.”

However, that didn’t go over so well.

“Well, Emily freaked out, saying I was being selfish and that Lily would be heartbroken if she didn’t go,” she continued. “My mom backed her up, saying I should ‘step up as an aunt’ because Lily looks up to me.”

“Now my whole family is treating me like I’m some kind of monster for prioritizing my own life over my niece’s Halloween,” she wrote.

“I feel guilty because I know Lily is excited about it, but I don’t think it’s fair that I’m expected to drop everything every time my sister needs a break,” she added, going on to ask if others thought she was justified in her refusal.

“Or am I really being selfish like my family says?” she asked.

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Many commenters chimed in, and the vast majority were in total support of her decision.

“You’ve got your own plans and it’s unfair for your sister to just assume you’ll drop everything for her,” read one reply. “Being a good aunt doesn’t mean being a free babysitter all the time.”

Another commenter recommended setting firm boundaries for the future.

“Tell your sister you will now refuse ANY request for assistance with less than X days of her ASKING for your help,” they wrote. “If she assumes your help, it’s an automatic no. If it’s less than X days barring legit emergency, it’s an automatic no. And most importantly, stick to it. Even if you’re at home watching Netflix. it’s an automatic no.”

Others wondered why no one else in the family stepped up to help out — including the girl’s mom.

“And why is the actual mom not being treated the same way for prioritizing her life over both of theirs???” one comment read, as another added, “She has a daughter and can’t do adults things before taking care of her daughter. Period.”