Kourtney Kardashian and Scott Disick their sons a joint 'Fast and the Furious' themed birthday party.

The on/off couple's two children, Mason, seven, and Reign, two, share the same birthday on December 14 and to mark the boys' big day they arranged a bash inspired by the street racing movie franchise starring Vin Diesel.

Kourtney's shared details and photos from the party on her Twitter and Instagram accounts and also on her personal website and app and revealed it is Mason who is the main petrol head in the family.

A post on her website read: ''Mason and Reign share the same birthday so every year we throw them a big joint party. This year, Mason wanted a ''Fast and the Furious'' theme complete with a monster truck bouncy house slide, mini race track, and the actual car from the movie. (sic)''

Some of the star attractions for the kids included a monster truck bouncy castle slide, a mini race track and an actual car that was used in one of the films.

Silver balloons spelt out 'The Fast and the Furious', whilst even the cutlery and napkins needed for the food were placed in car-shaped holders.

An hour into proceedings, a screening of the title movie was shown on a giant screen and later Mason and Reign were both presented with their own car-themed birthday cakes, with a car adorning the top of each.

The two siblings and their four-year-old sister Penelope loved playing on the bouncy castle with their mother and father and guests included their grandmother Kris Jenner and Jaden Smith - whose parents are Will Smith and Jada Pinkett Smith.