The cute snap showed 17-month-old Monroe leaning forward to give her twin brother Moroccan a kiss, with a caption that read: "'you love me & don't u forget it!' - A lil kiss from Ms. Monroe to Rocstarr."
Well, it looks like Mariah and husband Nick Cannon have been doing a good job at making sure there's no sibling rivalry between the pair!
While juggling her role as a mother and successful recording artist, the 42-year-old has now also become a judge on the latest season of American Idol.
But judging talent all day could be taking it's toll on Mariah's award-winning vocal chords, as she tweeted: "On vocal rest today after 2 days of non-stop talking on #idol auditions, then back to the studio tomorrow.. Can't wait!!!"
Fellow artists Nicki Minaj and Keith Urban will be joining the judging panel too, as well as American Idol regular, Randy Jackson.
We wonder if Mariah's twins will be visiting the set to watch their superstar mum at work. They're definitely too cute to stay hidden away at home!
Are you looking forward to this season of American Idol? Let us know in the comment box.
Watch Mariah's video for new single 'Triumphant' featuring Meek Mill and Rick Ross below.
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