A "Mickey Mouse Club" T-shirt Britney Spears signed 'I love you grandma' on is set to fetch up to $20,000 at auction.

Spears owned the shirt during her stint as a star of the kids show and gave it to one of her grandmothers as a gift. The clothing item will now be a highlight of the upcoming GottaHaveIt.com Rock & Roll Pop Art Auction, which starts on July 21.

The shirt is also signed by Spears' former Mickey Mouse Club castmates, including Justin Timberlake and Christina Aguilera.

-Britney Spears Pictures

(This news article provided by World Entertainment News Network)