If you mean just a normal male first love, not a TV personality, then like NL Senior, her name was Nancy. An absolutely stunning little blonde girl of 9 or 10 that I met at church in the choir.
My Mom took us to the movies and sat a few rows back to 'give us space'. I wonder what ever happened to her? Mmmmmmm.
From TV, I'd have to say it was Donna Reed.