Unless a grandparent has secured a court order granting them visitation, a parent is under no legal obligation to allow a grandparent to see their grandchild. In fact, barring a court order, a parent has the constitutional right to say no. If a court order has been granted, a parent will need to file a petition with the family court to modify or revoke a grandparent visitation order to stop the visitation. This matter can be more complicated if separated parents have differing views regarding whether the other's grandparents should be allowed visitation.
Every grandparent visitation case will depend on the specific facts and state law. In many states, grandparent visitation is only permitted if parents divorce, or one or both parents die. However, in most states, courts will consider grandparent visitation even if both parents are alive, married, and generally good parents. Like all family court matters involving children, a judge is going to make a determination of what is in the best interest of the child.