You have to apply in court and they will see what is best for the child.
see links below
If the father has legal custody the child should live with him. What does the custody agreement say?
They only have guardianship. If you didn't sign over custody, you have every right to get your children back.
Biusxx
For the grandparents to get the custody over the parent, they have to go through a court case and prove to their case to have custody.
when you're in full custody someone has control over you. Like the police when they have custody over you they have captured you and you're in their control.
Didn't you keep custody from him and he got the child back? see link
Some times but it all depends on the situation
If she's paid child support and depending on circumstances.
Canada. More specifically Stratford, Ontario, Canada
She should talk to an attorney specializing in family law to see what her options are.
Custody, not parental rights.