Indeed, the father is only 13, but this isn't as if this is a situation where two children are living in a home on their own trying to raise a child on their own. They would appear to have the support of both sets of grandparents and the wider family unit.
Not to mention that the parents of the new born child have a basic right to parent a child, using the support structures available, that hasn't been nullified just because they're young.
Doesn't make it acceptable though does it?