Kelly Osbourne jumps in middle of Twitter war between Joan Rivers and Rihanna about domestic abuse

CLEVELAND - Singer Rihanna isn't laughing at comedienne Joan Rivers after the two stars got into a feud on Twitter.

It all started on Friday, when Rivers tweeted, “Rihanna confessed to Oprah Winfrey that she still loves Chris Brown. Idiot! Now it's MY turn to slap her.”

The interview aired on “Oprah’s Next Chapter” the previous weekend. Rihanna told Oprah that she still loved her ex-boyfriend Chris Brown, who infamously beat her in 2009.

Rihanna jumped on the fact that Rivers cited an interview that was more than five days old.

The singer tweeted, "@Joan_Rivers wow u really do get slow when you're old huh?” That tweet has since been deleted, but Rihanna’s follow-up tweet, presumably aimed at Rivers, is still up: “Slap on some diapers."

That’s when Rivers hit back, figuratively. She tweeted: “Honey, @Rihanna, everyone knows: If he hit you once, he’ll hit you again. Read the statistics. PS – Love to have you on Fashion Police!” Note how Rivers does not miss an opportunity to serve her E! show.

Enter Kelly Osbourne, Rivers’s co-host on “Fashion Police.” Sticking up for her boss and staying classy at the same time, Osbourne tweeted, “W/ the greatest of respect 2 a young lady of whom I love please get a sense of humor @Joan_Rivers paved the way 4 all us opinionated ladies!"