They first collaborated on "Giving Myself," a beautiful track from her self-titled debut album.
"Luckily, her voice is ready to go at all times," Thicke told me earlier today. "She showed up, I had this great little song in the spirit of Whitney Houston, and she sat down next to me and I started singing it for her, and she loved it right off the bat. We got her behind the microphone and she Jennifer Hudson-ed it."
The two kick off their coheadlining six-week tour on March 31 in Albany, N.Y.
Thicke predicts the tour will be "very cathartic" for Hudson. "I think it's going to be the perfect thing for her to do, to get out there and get outside her head and feel the love she's been getting," he said. "She's a special lady."
Hudson began her return to the spotlight last month by singing the national anthem at the Super Bowl. It was her first performance—and public appearance, for that matter—since her mother, brother and nephew were murdered in the fall.
Thicke says there's a good chance he and Hudson will perform together during the tour. "Normally, by the time I leave the stage, I like to leave the stage," he said. "But I don't know. I might come back and play piano and sing backup."
But before the tour begins, Thicke will continue working on his new album. After we spoke, he was off to a studio session with über-producer Pharrell.
A self-described workaholic, Thicke said he and his wife of four years, actress Paula Patton, always make sure to find time for just the two of them. "She's also a very busy lady, which is why we try to schedule as much vacation and together time when we're both not working," he said. "But I pretty much work all the time, so that's why we have to take four or five days to go to Napa Valley or something like that."
With acting all around him (there's his wife, plus his dad is Growing Pains actor Alan Thicke and mom is soap opera star Gloria Loring), it sounds like Thicke is itching to get into the movies.
"It's in the blood," he said. "I wasn't very good at it when I was a kid because it didn't come naturally to me, but after being in a house with an artiste like my wife…it's like being around an acting coach. I wouldn't do anything just for the celebrity of it, but I would love to be involved with some great project."
He then laughed, "Watch, now you'll see me doing a horror movie with Paris Hilton."