So the feud between Kelly Osbourne and Lady Gaga started a long time ago, Kelly says that Gaga use to call her Fat! Well this past weekend it was Kelly's Birthday and Lady Gaga actually bumped into Sharon Osbourne and they took a photo together holding a cake that says "Happy Birthday Kelly" - and they posted it online....welllll Kelly didn't like that one bit! Check out some of the stuff she tweeted below! We're sorry for the bad language!
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