The pair have been friends ever since they did a duet together at the Brit Awards in 2005 and he has been helping to put a smile back on her face after it was revealed she was at the centre of a kidnap and murder plot.
A source said to UK newspaper The Sun: 'Robbie and Joss have been mates for years. He got straight on the phone to see if she was OK and invited her to Wales.
'She's still in shock but Robbie did his best to put a smile back on her face. His cheeky chappy side was in overdrive when they met up after the gig.
'She was making light of it too, joking that it's been like an episode of Midsomer Murders.'