OITNB 's Samira Wiley, Lauren Morelli Welcome Baby Girl George Elizabeth: 'Best First Mother's Day'

Samira Wiley/Instagram; Inset: Michael Kovac/Getty Samira Wiley and Lauren Morelli's daughter George

Surprise — Samira Wiley and Lauren Morelli are moms!

The Orange Is the New Black actress and writer announced the birth of their first child together, daughter George Elizabeth, on Sunday — the pair's first Mother's Day.

"Happy 1st Mother's Day to my beautiful wife, who four weeks ago today after laboring for almost 3 days gave birth to our first child — our gorgeous daughter, George.💜," Wiley, 34, captioned an adorable photo of their newborn grasping both her moms' fingers.

"Welcome to the world, babygirl. We love you and we thank you for giving us the best 1st Mother's Day two ladies could ask for," she continued, sharing George's birthdate: April 11.

Posting the same snapshot, Morelli, 38, wrote, "4 weeks ago today, our daughter came into the world and changed everything. We are so happy, so grateful, and so tired. George Elizabeth, 4.11.21 ❤️."

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Michael Kovac/Getty Lauren Morelli and Samira Wiley

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The pair tied the knot in Palm Springs, California, in 2017, wearing two custom looks by Christian Siriano: a structured, full-skirted ball gown for Wiley and a jumpsuit complete with cape and ornate collar for Morelli.

The Palm Springs location was special to the couple, as it was where the OITNB writer popped the question the previous October with a dazzling yellow-gold engagement ring featuring an asscher-cut diamond.

In October 2017, Wiley told PEOPLE that married life has taught her "that it's not just about you anymore, but about you and your partner as a unit."

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"Life is now about navigating it together," The Handmaid's Tale actress added.

Wiley marked the couple's four-year wedding anniversary in March, sharing a black-and-white image of the brides as they stood in front of all their guests at their reception.

"4 years down. Whole lot more to go. Life is f---ing breathtaking with you, @lomorelli," she wrote. "Happy Anniversary, babygirl."