'Hero' singer Mariah, who married Nick in the Bahamas on 30 April in 2008, shared photos on Twitter last night as she enjoyed the special family occasion.
Nick publicly declared his love for wife Mariah in a touching Twitter post. "Wow I am the luckiest and most blessed man on the planet," he said. "Today is my 6th anniversary of being married to my dream girl! And everyday just keeps getting better!
"Happy Anniversary to my amazing wife @mariahcarey. I Love You," he continued.
In one photo, the loved-up couple looked smitten as Nick planted a kiss on Mariah while holding on to their anniversary cake.
Meanwhile, 44-year-old Mariah was all smiles as she sat on his lap while clutching a large fluffy teddy bear.
Seeing as they were sharing their special day with fraternal twins Monroe and Moroccan, Nick and Mariah made sure to spoil them with plenty of gifts too!
Nick who bought Monroe and Moroccan miniature vehicles, showed off the twins' presents with a photo on Instagram. Captioning the snap, he said: "They grow up so fast! They're already driving!"
After posting tons of photos of their special day, Nick later took to the social networking site to write another message about his family.
He said: "4/30 was amazing! Happy Birthday to my greatest blessings in the world and Happy Anniversary to the beautiful woman who gave them to me! #Family #Love #LookAtMyToughGuy #RocAboutToSetItOff."
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