'Parental rights' is something of a myth. In fact, the courts are only concerned with the rightsof the child.
All things being equal a court would wish for the child to be with it's mother, but if the mother has failed to care for her child properly, the child will be placed in the care of someone else who can better meet the needs of the child.
It's a balancing act but from what you have written, it would seem unlikely your daughter would succeed in an action to gain a residency order.