Source: 21st birthday is a special celebration for one waiting list family | Post-Gazette

For families in Pennsylvania who have a child with an intellectual or developmental disability, a 21st birthday can be an unhappy milestone — an end to the vital services their children receive.
Until age 21, the care they receive, such as behavior and occupational therapy, is considered a federal entitlement — that is, Medicaid has to pay for it. At 21, that entitlement ends, which can lead to a “cliff” effect of a sudden cutoff of services and being put on a waiting list until additional funding is available.