Kris Jenner cried for days after learning of Kim Kardashian's sex tape.

The reality star ''literally fell apart'' when X-rated footage leaked in 2007 of her daughter engaging in sexual acts with R&B singer Ray J, who was her boyfriend at the time.

Speaking during an appearance on Joan Rivers' web show, 'In Bed With Joan', she revealed: ''I cried myself to sleep. I don't think anything can prepare you for something like that when it comes to your daughter. I had to go into a room and cry for a couple days and say, 'OK, pull yourself to-f***ing-gether because you have to be here for all these kids and your family, and you have to show them as an example how to get through this.' ''

Kim - who is now engaged to Kanye West, with whom she has a baby daughter North - initially sued adult entertainment company Vivid Entertainment, who purchased the tape to release as an adult DVD 'Kim K Superstar'.

But she eventually settled out of court for a reputed $ 5million. The exposure the tape provided Kim gave her profile a massive boost and she and her family landed their own E! reality show 'Keeping Up with the Kardashians' later that year.

Kris has been responsible for masterminding the successful careers of her daughters, Kim, Khloe and Kourtney, but insists she doesn't take 50 per cent of their earnings like most Hollywood managers.

She explained: ''I said to the girls, 'I love what I do. I think I have a lot to offer. I think I'm good at what I do but my thing is I would never take that for my own.' ''