perhaps the mother is a mardy cow and makes access difficult?
that's the excuse that my FiL makes, when asked why he never saw any of his four children,
he then goes on to tell us how "mad" she was, totally off her rocker, complete unhinged,
he's right she was, partly driven there by his endless affaires,
If he an adult found it impossible to deal with her why did he think four small children would on their own,
those children went through hell, on their own, with no cavalry coming over the hill,
Unless a parent is a danger to a child, than there is no excuse not to see and support them.
OP your friend is in for a rough ride, I hope she has supportive people around her.