Is it normal to be infatuated with the mother of a girl i know?

I was never attracted her daughter, but I am picky. I am in my 20's and I am not a teenager. Then about a year and a half ago I saw her mother. She is twice as old as I am! But hey she looks like a super model. I think about her a lot. She has an amazing body, and a really cute face. She does not look old. I love who she is, her job and how she dresses. She is not married. I don't really know her daughter. I saw her (yum) last night and almost went over and talked to her. I dream of being with her in her life. Its crazy. I know it is impractical.