Nick Cannon has paid tribute to his estranged wife Mariah Carey on her first Mother's Day since they split last year (14).

The stars are parents to twins Moroccan and Monroe, who turned four last Thursday (30Apr15), on the former couple's seventh wedding anniversary.

Despite their split, Cannon still has love and respect for the pop superstar, and he took to Instagram.com on Sunday (10May15) to post a photo of Carey alongside their two children.

He added the caption, "Gotta represent for the Mother of my children. She is such a wonderful, thoughtful, festive, loving and nurturing Soul. I will forever be in debt to you for blessing me and the rest of the world with Roc & Roe. A true #Queen Will love you always @MariahCarey #HappyMothersDay."

Cannon filed for divorce in December (14), but the two have publicly shared photos of them spending family time together over the past few months.