Kourtney Kardashian is pregnant.

The reality star and her long-term partner Scott Disick are reportedly expecting their third child together.

The 'Keeping Up With The Kardashians' favourites are excited about giving their children Mason, four, and Penelope, 23 months, a little brother or sister in December.

A source told Us Weekly magazine: ''It was planned. Kourtney wants to have a handful of kids.''

Another insider added: ''She is only a few months along.''

The couple have decided to wait until the baby is born to find out the gender.

A third source explained: ''They don't know the gender yet. They just want the baby to be healthy.''

Kourtney and Scott have been together since 2007 and their famously tempestuous romance is publicly documented on the Kardashian family's numerous E! reality shows.

The 35-year-old star recently credited prioritising with helping her juggle work commitments and family life.

Asked how she juggles her schedule, she said: ''Knowing my priorities. Nothing comes before my children. I find that putting everything else in order of importance also helps to get everything done.''