Problems with balance and coordination are very common when they have dementia. It can happen at any stage. It just depends which areas of the brain are affected by the dementia.

Thank you...I will check with his dr.

Doesn't have to be 7...could be overmedicated, or hypotension, or muscle weakness, OR some change in the brain. Balance ability is in a certain part of the brain. Your Dr can help pinpoint the cause. He may recommend PT.