Mariah Carey has credited playing shows in Las Vegas with helping to keep her family happy and healthy.

The singer shares six-year-old fraternal twins Moroccan and Monroe with her ex-husband Nick Cannon, and the Emotions hitmaker admits her kids are often heartbroken when she leaves home to perform concerts.

"They have to understand sometimes when I go to work, they're like, 'I don't want you to go to work! Stay home! Don't go to work!' and then I feel guilt-ridden, but it's all right," she tells U.S. news show Extra. "They get used to it, and then when we spend time together it's more special."

Mariah is currently wrapping up the final shows in her #1 to Infinity concert residency in Las Vegas and to her surprise, performing in Sin City has actually improved her children's perspective of their mother's work.

"They love it in Vegas," she notes. "They're always asking about it."

Ahead of the end of her concert residency in July (17), Mariah is putting her all into the final performances.

"It (the #1 to Infinity concert) starts from the beginning of my career, so I start with Vision of Love - my first single - and I go all the way through the rest of the 18 number-ones," the 47-year-old shares, confessing the prospect of concluding the series with a bang is "really exciting" for her. "I'm looking forward to it. I love going there (onstage in Vegas). The fans are great - they come from all over the world."

After her residency wraps, Mariah will be hitting the road with Lionel Richie, but she has no idea what the duo's sets will be like on their All the Hits Tour.

"I'm not sure what we are doing with singing together," she admits. "My set is 60 minutes."

Mariah and Lionel will play 22 dates in the U.S. and Canada on their joint trek, which kicks off in Oakland, California on 21 July (17).