The 'Hero' singer looked in high spirits as she left the Bar Sfizi Pizza restaurant in Tribeca, New York on Tuesday (26 August), accompanied by her and Nick's twins Monroe and Moroccan.
Mariah was chic in a patterned monochrome wrap dress and oversized hat, and beamed for the photographers despite the recent rumours surrounding her marriage.
TV host Nick confirmed last week that he and Mariah have been living separately for a few months after stumbling into a "rough patch" in their marriage.
He denied it was caused by infidelity and said the main priority for the couple at the minute is the wellbeing of their three-year-old twins.
Mariah, meanwhile, has not publicly commented on the state of her marriage, although a source told E! News that the singer was annoyed Nick had released comments without telling her, saying she would have preferred a joint statement.
A rep for Mariah has only said she will not comment on the star's personal life.
While Mariah was seen looking glamorous and happy yesterday, it was a different story across town, where Nick was pictured looking downcast.
The America's Got Talent host was snapped wearing a casual grey tracksuit as he left a Manhattan office building.
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