Slowing Down

My daughter is slowing down. She realizes there are some things she just can't remember or missed entirely. It worries her. She just stares off. I often look into her confused eyes and ask what she's thinking about. She responds by saying I'm trying to remember. Lately its been very insignificant things...Like the day she found out her sister had a game cube. She said, "Where was I when my sister got a game cube? I just say she bought it used last year....she just stares off. I feel really bad for her.