Kelly Osbourne and Lady Gaga are not in good terms since 2009 after Kelly criticised her for disrespecting her fans by not attending Grammy Awards.
Later that year, she told talk show Alan Carr that she thought Lady Gaga was pregnant when she wore a burkha style outfit.
Lady Gaga's fans began to show hatred towards Kelly Osbourne.
Kelly then wrote,'Don’t say, "When you see bullying, intervene," while letting your fans send me death threats'.
'If my fans did that, I would not stand for it. You can say whatever you want with your millions of monsters.'