It is possible for grandparents to be given visitation rights in Maryland, thanks to changes made to the law back in 1993. The Maryland Annotated Code now notes that grandparents can ask for these rights and may be given them if it falls in line with the best interests of the child.
In cases where parents have no objections, this isn't hard at all. It is unlikely that the court would rule that it is in a child's best interests not to see his or her grandparents.
However, if there are objections from the parents, it gets very difficult indeed. In fact, experts have said that courts are more likely to side with the parents in these cases the vast majority of the time. The only exception is when it's very clear that the child's best interests will be ignored or that the child will be harmed in some way by not seeing the grandparents.
In some situations, rulings are also over schedules and timing. For example, there was one pivotal case—Brice v. Brice—where the parents were fine with the grandparents getting visitation rights; they just did not want the court to tell them they had to stick to a specific schedule, which is what the court had done.
The mother protested, and it was eventually determined that her rights were violated by the schedule; the grandparents could see the child, but they couldn't be given any specific times for that interaction, as that imposed on the freedom of the mother.
Those who are involved in these cases need to know all of their legal options, as cases between family members can be very complex and emotionally charged.
Source: The People's Law Library of Maryland, "Grandparent Visitation Rights," accessed Nov. 05, 2015