Katharine Mcphee has found the death of her nanny "tough".

The 39-year-old singer left her and husband David Foster's 'Hitman' tour early on 11 August after Yadira Colito was killed when she was hit by a vehicle that had accidentally been driven into a customer reception area at a car dealership and the former 'American Idol' star - who has two-year-old Rennie with her spouse - is still coming to terms with the tragedy.

David told 'Entertainment Tonight': "It's been tough for her. Yeah, it's been tough. She's managing."

Katharine added: "Thank you."

A month on from the shocking crash the couple are back on the road and are working on a continuation of their 'Christmas Songs' record.

David explained: "We got a nice response from the first seven songs so we thought, 'Oh, people are kinda digging this.' "

Katharine added: "Volume two, we'll just complete the whole thing. A couple of my girlfriends are like, 'You're doing another Christmas album?' I'm like, 'No, this is a completion of the first Christmas album.'"

The 'Smash' star loves recording with her producer husband.

She said: "It's pretty fast and furious 'cause he gets so focused.

"There's not a lot of messing around. It's like you see the back of his head for a lot of the day honestly 'cause he just drills down.

"But for me, my favourite part is obviously being in the recording booth when he's recording my vocals. I don't see anybody, but I just hear his voice and he's always been the best to record vocals."

David has previously worked on festive albums for the likes of Michael Buble, Celine Dion and Josh Groban and finds the projects easy.

He said: "Believe it or not it's always fresh.

"Like, you could give me a song title right now of a Christmas song, I'd go to the piano. I could do it probably thee or four different ways without really thinking about it. In a jazzy way, in a country way, in a classical way, in a slow way, in a fast way. And so I just mix it up."

Katharine and David married the knot in 2019 before having Rennie in 2021.

David is also the father of daughters Allison, 52, Amy, 49, Sara, 41, Erin, 40, and Jordan, 36, from previous relationships.