Well, I did say it was worst case. But it does look like the mom-daughter relationship is not very good there. Like I said, I'm sure her mom simply chose not to fight for custody, and Sam likely took that as Mom doesn't really want her, regardless of what the actual reasons may have been; for example, maybe her parents realized a long bitter custody battle would be really bad for Sam, and decided that Jim should be custodial parent, since he seems to get along best with Sam. Somewhat against the general trend, but possible.