I agree with Vicki.

And so does this site:
Quote
Names of relationships only when they are a part of or a substitute for a person's name. (Often this means that when there is a modifier, such as a possessive pronoun, in front of such a word, we do not capitalize it.)
  • Let's go visit Grandmother today. Let's go visit my grandmother today.
  • I remember Uncle Arthur. I remember my Uncle Arthur. My uncle is unforgettable.

This also means that we don't normally capitalize the name of a "vocative" or term of endearment:
  • Can you get the paper for me, hon?
  • Drop the gun, sweetie. I didn't mean it.

Do you know the most surprising thing about divorce? It doesn't actually kill you, like a bullet to the heart or a head-on car wreck. It should. When someone you've promised to cherish till death do you part says, "I never loved you," it should kill you instantly.

- Under the Tuscan Sun