I was never a fan of Phil but you can say two things about him:
1) he was protective of his kids 2) As much as he hated Ian and how Ian hated him, Phil questioned it when Stella said Ian had abused him. Stella was using their rivalry against him and it backfired. He knew Ian that well that he wouldn't hurt another child and especially Ben.
Phil should have listened to Ben, he never liked Stella. Peggy was a good grandma. Phil didn't like Ian but knew he'd never hurt his brother. Of course it was Stella. And she was crazy to say his mum and dad, as if she was Ben's mum 😂