That's just it. Tieflings aren't tribal about Tieflinghood. They're lumped together but apart from lineage, have little in common. Not a strong community. They look like they'll disband should they reach BG.
Asharak, Wyll, granny cook, Rikka and the bard collectively look after them. But apart from Rikka and Doni there's no caring adult/child bond. Guess that's the space Mol fills.
I think you are forgetting that half the Tieflings are lined up outside the ceremony trying to get a kid back, including her parents.
