In-laws pressure 19yo to adopt 5yo; he says, 'she's not my responsibility.'

Based on the situation described, the OP (19M) took responsibility for his younger sister Calla (15F) after their father and stepmother passed away, declining to take custody of their stepsister Lacey (5) who was placed with their paternal grandparents. Despite being pressured by the grandparents to include Lacey in their care, the OP made it clear that Lacey was not their responsibility. The grandparents persisted in their demands, prompting the OP to assert boundaries firmly, leading to further accusations of selfishness and cruelty.

Given the circumstances, the OP’s decision to prioritize his own sibling, Calla, whom he could adequately care for, seems reasonable. The grandparents’ insistence and guilt-tripping tactics overstepped boundaries, especially considering the OP’s age and circumstances. Therefore, based on the information provided, the OP does not appear to be the asshole (NTA) in this situation.

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