'Funnily enough, Joseph never seemed to be hungry, so I had to eat his share,' says Daniel. 'But after all, what are friends for ?'
At 27, Daniel's special pal Joseph has been replaced - on television anyway - by the highly visible John Nettles. For as Sgt Gavin Troy, Daniel is sidekick to John's Det Chief Insp Tom Barnaby in Midsomer Murders.
'I've always been a big fan of John's,' says Daniel. 'I even used to play Bergerac games at school. Now we get on really well both on and off screen and I think you can see that reflected in the show. I really do respect John tremendously, both as a person and as an actor.'
If there's any competiveness between the two, its jokingly centred on who has the bluest eyes.
'Yeah some people have said we have a similar look,' admits Daniel, who grew up in Stockton-on-Tees, where his Dad Luke Casey, a former television journalist, hosts a magazine programme on the local ITV station called The Dales Diary.
After joining youth theatre at 14, Daniel decided acting was just the job for him. 'A couple of girls at school got me and my mate Damian along because there weren't enough boys there,' says Daniel. 'They were doing Bugsy Malone and I got the part of Bugsy. I thought that must be a good start.'
In his 2nd year studying English at Durham University, he surprised his family by quitting to go on tour in an award winning play called Dead Fish. It might have seemed like a risky move but it couldn't have turned out better. Spotted by a casting agent, Daniel landed the part of the young policeman Anthony in the BBCs acclaimed Our Friends in the North, a role which became a springboard for his acting career.
'It was a lovely part, a great showcase because so many people saw it,' says Daniel, who went on to work in The Bill, A Touch of Frost, The Grand and the Catherine Cookson mini-series Wingless Bird before landing the role of Troy.
At the second audition there was no other actor there but me, so I thought ah, this is looking hopeful. When I left the building, I walked down the road and went into a phone box and rang my agent, and she said, "You've got it!" so that was lovely.'
Now based in West London, Daniel's a Middlesbrough supporter and although he'll happily talk football all night, his private life is off limits.
'I don't really want to talk about my girlfriend,' he says. 'She's not in the acting business - she works in textiles - and she's really quite shy.'
Whatever happened to Joseph ?
'Oh, he disappeared once I went to school,' says Daniel. 'Mind you I still miss the extra sweets.'