Remembers the war but not my name

Every week my father has forgotten a little more of the present but discloses more of the past. Today he told me a lot about naval strategy in ww2, because he was in the Navy.

"They had us hopping from island to island," he said, suddenly, clearly , "and it wasn't till afterwards we discovered they were expecting a 50% casualty rate."

But he can't remember my name.

My sister brings him a half of bitter from the pub and he drinks it through a straw. I'm not sure that these days he remembers how much he likes bitter...