Jessica Simpsonis celebrating Father’s Day with a special message for husband Eric Johnson.

The fashion designer, 38, shared a sweet family photo featuring Johnsonwith their three children, and penned a note praising him as the “best father in the world.”

In the photo, which appears to be taken in a hospital, Johnson, 39, cradles newborn daughter Birdie Mae in his arms while proud siblingsMaxwell Drew, 7, andAce Knute, 6, look on smiling.

Simpsonmarried the former NFL playerin July 2014. They welcomed daughter Maxwell in May 2012, and son Ace in June 2013.

Jessica Simpson Instagram

jessica-simpson

Theirthird bundle of joy, Birdie, was born on March 19, Simpson’s rep exclusively confirmed to PEOPLE at the time.

“We are so happy and proud to announce the birth of our perfect daughter, Birdie Mae Johnson,” Simpson later wrote on social media as she shared a photo of her older children meeting their new sibling for the first time.

Simpson shared a photo of Johnson’s sweet card, which read, “Dear Jess, You have literally taken motherhood to the next level,” his card read. “You have given us three kids and I could not be more grateful or in awe of you. You make every one of my days special. I love you with all my heart. Love, Eric.”

Jessica Simpson/Instagram

Jessica Simpson

She also received a card from Maxwell and Ace, who wrote that they had the “greatest mom in the universe.”

“Dear Mom, You could not be more beautiful, more funny, more loving, more fun,” the kids’ card read. “We love you to infinity and beyond and tie a couple loops around the moon on the way back and then back to your heart. That’s how much we love you.”

Shortly after Birdie’s birth, Simpsonopened up to PEOPLEabout adjusting to life with three kids, and the difficulties that come along with it.

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“Three is challenging. We are trying to get into the groove and make sure all three kids are getting equal attention,” she said. “It’s more than a full-time job right now.”

Still, she admitted that Birdie “makes our family complete.”

“Someone once told me to keep in mind that everything is a phase with infants and kids … trying to remember that fact, and celebrate the small victories,” she told PEOPLE.

source: people.com