Eva Amurri and estranged husband Kyle Martino welcomed their third child, son Mateo Antoni Martino, on March 13

Eva Amurri is so in love with her newborn baby boy, Mateo Antoni.

On Saturday, the actress shared a series of adorable photos of Mateo — whom she welcomed with her estranged husband Kyle Martino on March 13 — celebrating his milestones at 1-week-old.

” 🌿One Week Old 🌿 (a day late…which is pretty good for a third kid 😆),” the mom of three joked on Instagram Saturday. “Mateo is eating like a champ, sleeping for 3-4 hour stretches, crying, pooping, hiccuping, and stealing our hearts with his big blue eyes ☺️.”

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Amurri, 35, admitted that while she “knew we would love him deeply, [she] didn’t know how quickly life would be unimaginable without him.”

“Soaking in the impermanence of all things Newborn, sniffing a lot of baby aroma, and thanking my lucky stars for this gift of a boy,” the mom of three wrote, adding the hashtags “Happily Eva After,” “Mateo Antoni” and “One Week Old.”

In the first picture, Mateo can be seen laying down (in too-cute donkey pajama pants!) next to a botanical sign that spells out “Mateo,” while the second picture is a close-up of her baby boy.

Amurri — who shares 3-year-old son Major James and daughter Marlowe Mae, 5½ with Martino — also added several pictures to her Instagram Story enjoying some quality time with Mateo.

Eva Amurri's newborn
Eva Amurri's newborn

In two pictures of Mateo, shared on her Instagram Story, the child can be seen laying on his mother’s legs. “Sleepy newborn phase [is] OVAH,” the “Cute Newborn Phase [is] forever,” Amurri wrote.

Martino, 39, also shared several videos of himself playing with their kids outdoors.

Amurri confirmed to PEOPLE on Thursday that she and Martino were legally single when they welcomed Mateo, revealing that they finalized their divorce a month and a half ago. According to court documents obtained by PEOPLE, the finalization occurred on Feb. 4.

Eva Amurri's newborn

As exes Amurri and Martino are spending time together amid the coronavirus outbreak, she called herself the “queen of social distancing” in another photo cuddled up to her newborn.

Both parents have been sharing photos and videos on their social media since the birth of their third child.

In two posts to Martino’s Instagram Story on Thursday, the NBC Sports analyst was seen holding his newborn close as little Mateo looks around with wide, seemingly curious eyes. Atop one image, Martino added a banner GIF that read, “All you need is love.”

Kyle Martino, Eva Amurri

Meanwhile, Amurri shared a snapshot of herself and daughter Marlowe snuggling in bed with baby Mateo on Thursday, as well as a video of the family’s newest addition dressed in dinosaur-print pajamas. The baby blogger captioned the latter footage, “Happy Due Date, baby boy!”

Although Martino was not physically present for Mateo’s birth, shortly afterward, the exes have been spending some quality time together as a family.

Eva Amurri
Eva Amurri and Kyle Martino with their kids
| Credit: Eva Amurri/Instagram

“Our sweet little boy came Earthside yesterday, peacefully at Home,” Amurri wrote on Instagram Saturday, alongside photos that showed herself and Martino in bed with their three kids. “We are all SO in love.”

In his own celebratory post, Martino praised his ex for being a “rockstar bringing this incredible gift into the world,” while also including the hashtag “#ModernMartinoFamily” and a string of red heart emojis.