The poster, a 23-year-old woman, is conflicted after her 13-year-old half-sister opened and used one of her unopened birthday gifts without permission. Despite the sister already having a large collection of perfumes, creams, and beauty products, she frequently borrows—and often finishes—the poster’s items. When confronted, she defended herself, saying she couldn’t wait to try the gift, which included hand cream and nail care items.
The poster told her sister that not everything she owns automatically belongs to her, but this caused tension. The sister’s mother criticized the poster for being “selfish” and claimed siblings should share everything. Now, the poster wonders if she’s wrong for trying to enforce boundaries. Many would agree she’s not the A-hole—she’s simply asking for respect and privacy, especially since her sister’s behavior has repeatedly crossed lines of personal ownership.
AITA for trying to set a boundary with my little sister after she opened my birthday present?
