Kourtney Kardashian admits things got "intense" between her boyfriend and sister when she was filming her new reality TV show.

The socialite, boyfriend Scott Disick and sibling Khloe lived together while shooting the E! series 'Kourtney and Khloe Take Miami' and the housing arrangement led to several combustible situations.

Appearing on the 'Late Show With David Letterman', Kourtney said: "He (Scott) got a little crazy in Miami. Khloe and Scott living together under one roof - we were all living in a suite - it's just not a good idea. Things got a little intense."

Host Letterman then joked Scott might need help for his apparent anger issues, saying: "He seems like he might have a little punk in him?"

To which Kourtney - who has a five-month-old son Mason with Scott - replied: "He has been working on that problem."

Letterman responded with the quip: "The 12-step programme for punks, good luck!"