AITA for not letting my “sister” move in with me?

Family dynamics can be tricky—especially when stepparents and stepsiblings are involved. But at what point does setting boundaries make you the bad guy? One Redditor found herself in the middle of family drama when her stepmother, Brittany, insisted that her adult daughter, Stella, move in with her. The issue?

OP barely knows Stella, is planning to start a family with her fiancé, and simply doesn’t have space. When she refused, the situation escalated, with her father cutting off contact and calling her selfish. Did OP make the right call, or should she have been more accommodating?

‘AITA for not letting my “sister” move in with me?’

Dr. Ellen Kramer, a psychologist specializing in family relationships, explains that setting boundaries in blended families is often met with resistance—especially when one side tries to force a “family bond” that doesn’t exist.

“In situations where stepparents attempt to impose relationships rather than letting them develop naturally, it often leads to resentment,” Dr. Kramer says. “It’s important to respect the individual’s comfort level and personal space.”

OP’s refusal isn’t about being unkind—it’s about prioritizing her own needs. Dr. Kramer adds that Brittany’s expectation that OP should house her adult daughter is both unreasonable and manipulative.

“She’s expecting OP to take responsibility for someone she barely knows, despite having a full household of her own to manage,” Dr. Kramer explains. “That’s not fostering a healthy family dynamic—it’s overstepping boundaries.”

Here’s what people had to say to OP:

Most people sided with OP, agreeing that she has zero obligation to house someone she barely knows—especially when she is about to start her own family. Many criticized OP’s father and Brittany for trying to force a relationship that doesn’t exist and for expecting OP to take on financial responsibility for an unemployed adult. Some even pointed out the irony: if Brittany and OP’s father think Stella needs help, why don’t they take her in instead?

At the end of the day, OP’s home is her space. No one has the right to dictate who she must house—especially not for someone she barely knows. What do you think? Have you ever been pressured to take in a family member? How did you handle it? Let’s discuss in the comments!