What an irresponsible algorithm filling response to that girl.
As you say, there's absolutely no background given whatsoever but Melvyn is straight in there, making negative assumptions about the Mother, sibling and Grandma.
She doesn't know a single thing about the girls situation - whether she's safe, whether there are welfare concerns by being estranged from her Mother etc - but she instantly tells the girl to do what's right for her.
When I was a teenager I thought it was right for me to hang around with a very dubious set of people and get plastered as much as possible, which inevitably led to me getting in trouble, and if I'd had someone willy nilly tell me to do what's 'right for me', my teenage brain would've thought I was being given the green light to be as wreckless as I wanted without thought for consequence.
This is Melvyn's attempt to look as if she's 'helping' someone. We all know she reads here and she knows we think she's doing sod all to help people, because it's not really about helping anyone, so she's decided to go ahead and answer a very vague question.
And she picks one relating to a child.
Dear God. There is so much more she could've advised her to do rather than 'just do what's right for you'.