Kelly Clarkson just couldn't contain her joy during her first Mother's Day.

The "American Idol" alum shared that her husband, Brandon Blackstock, made Sunday extra special with a handmade gift from their baby daughter River Rose. "My husband had this little nugget scribble on a Mother's Day card for me today," Kelly captioned a photo of her adorable tot. "I cried."

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Brandon has two kids, Seth and Savannah, from another relationship and Kelly seems to have adjusted quite well into her role as step-mom. "Best gifts I've been given are all 3 of my kiddos #River #Savannah #Seth," she wrote. "Being a mother is the greatest thing I'll ever do. My career inspires me but my family gives me this constant state of euphoria that is all consuming and ever growing and sometimes hard but completely worth it."

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The 33-year-old singer also paid tribute to all the mothers out there. "Happy Mother's Day to every single mama on the planet!" she wrote. "You're beautiful! You're inspiring! And you create the future!! What the hell, that's so amazing?!"

This wouldn't be the first time Kelly has gushed over motherhood. "I've accomplished a lot, but I guess the biggest success I want is that whenever I die people will say, 'She was so successful as a mother, and as a wife.' That’s kind of my big goal," she told People magazine in February. "I never thought I was going to be a mom, so it's very much changed my world in the most awesome way."