a bone disease that causes the bones to become weak and brittle. Osteoporosis, in and of itself, isn’t usually painful. Typically, the condition doesn’t present symptoms until a fracture occurs.

Black was born with osteogenesis imperfecta (OI), a genetic or heritable disease where your bones break extremely easily, often with no obvious cause ... wrote in his book Brittle to Unbreakable.

Related: Jay & Pamela: Couple with Brittle Bone Disease Thrive Despite Limited Mobility: 'You Don't Use It, You Lose It' (Exclusive) Never miss a story — sign up for PEOPLE's free daily ...