My Dad

My Dad is not doing too well, his brain is bleeding and he lost his memory. My Mom is trying to teach him "L" for Lobby and "2" for their floor. He disappeared in the lobby and she found him on the 10th floor.
I talked to him on the phone and he sounded OK except he told me how he's trying to learn "L" and "4". He hesitated and seemed to know that wasn't quite right.
His 80th birthday is in August.