Today’s Best Tweets: Katy Perry Wants Fans to Donate to the ASPCA for Her Birthday

Today on Twitter, Katy Perry was celebrating her 27th birthday by asking her friends and fans to please donate to the ASPCA if they were able. There are many other Kitty Purry's that need homes too! Both Camryn and Rebecca Black were wishing Perry the best on her special day while Missy Elliott and Ne-Yo were sending wishes to Ciara as it was her birthday too! Adam Lambert and Lea Michele were both jamming to the new Kelly Clarkson record, 'Stronger.' Usher went into his son's classroom today to help the little guys and girls carve pumpkins (so cute!), and Chris Colfer is planning to visit a friend in Egypt. And lastly, Mayer Hawthorne may or may not be filling in for David Letterman? Come again? See what your favorite stars were chirping about today!