Translation:The child has parents, and they love him.
As far as I understand it:
infano = child (gender neutral)
infanoj = children (gender neutral plural)
knabo = boy
knaboj = boys (same as "male children")
knabino = girl
knabinoj = girls (same as "female children")
Infanino isn't a word. And it doesn't mean female child. Knabino does.
So yes, ŝin would be perfectly acceptable here.