In this episode, Chris and Xand continue to explore the power of saying 'no', this time focussing on defiance in parenting in childhood. They’re joined by behavioural scientist and physician Dr Sunita Sah from Cornell Univeristy.

If you want to get in touch, you can email us at whatsupdocs@bbc.co.uk or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken
Guest: Dr Sunita Sah
Producer: Emily Bird
Executive Producers: Rami Tzabar and Jo Rowntree
Editor: Kirsten Lass
Assistant Producer: Maia Miller-Lewis
Tech Lead: Reuben Huxtable
Social Media: Leon Gower
Digital Lead: Richard Berry
Composer: Phoebe McFarlane
Sound Design: Melvin Rickarby

At the BBC:
Assistant Commissioner: Greg Smith
Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.