16-year-old refuses to move back in with her widower dad after he abandoned her for stepmom and step-siblings: 'My aunt is a way better parent than my dad was.'

He is not going to win Father of the Year.

You can't force a sibling relationship between two stepchildren, and you can't force a child to accept their stepmom or stepdad as a parent equal to their mom and dad. While it can be difficult for a parent when their child seemingly stubbornly refuses to accept their new partner and their children, it is so much harder for the kid to be gaslit into treating people who are functionally strangers as close and beloved family members. Emotional closeness between blended family members has to be formed over time, and there's a good chance it won't happen at all, and that's okay. A kid whose age is in double digits isn't going to accept a new parent into their life as quickly as a toddler, and there's nothing wrong with that. If two stepsiblings have a relationship that's closer to that of a roommate than to that of siblings, you shouldn't demand that they become more emotionally attached than they are. That's just going to drive them further apart.

Sometimes, an aunt, uncle, or grandparent may be closer to a kid than their stepparent, even though the kid lives with their stepparent. There's nothing wrong with a kid having different levels of closeness with different family members, and it only makes sense that they're going to be closer with someone they've known their whole lives than they will be with, it bears repeating, functionally a stranger.