The Kardashian kids are using their dad's widow, claiming she's been illegally selling portion of a diary they inherited.

Kim, Kourtney, Khloe and Rob are suing Ellen Pearson who was married to their father, Robert Kardashian. 

They claim that their father had a diary that contained very personal details about the klan and has been selling tidbits to tabloids. 

The deceases Kardahsian, famous for reaping OJ Simpson, allegedly elf the diary to his kids in his will.

Among the info that Ellen allegedly sold included - Kris allegedly hit Kourney and Kim and also threatened to kill Kim…. and Rob was locked in a car while Kris was out on a date.

The lawsuit alleges the diary is owned by the Kardashian kid and Ellen is infringing on their copyright and demands the return of the diary and family albums, as well as damages.