Hi TheLioness789,
It’s understandable that you’re feeling conflicted. You don’t owe his side of the family anything, especially not your peace. If you’re not feeling comfortable opening the card then you don’t have to. If or when the person the card is for is old enough to weigh up the situation and make a decision themselves, you could have a hypothetical conversation with them about what they would want. That could inform your decision about what you do and help you to decide. If contact with his family is going to put you at any risk of harm or distress though, it’s okay to put your wellbeing first. You don’t have to tell his family you haven’t passed the card along.
Take care and keep posting,
Lisa