Tom, 40, took to his Instagram Stories to reveal that he was getting a new tattoo, although by tagging his girlfriend, it implied that he was getting a couple's tattoo.
However, the following snapshot revealed that it went beyond your typical inked tribute to a partner, as he and 37-year-old Kaley had gotten matching tattoos in honor of not just their relationship, but also their newborn daughter, Matilda.
They'd each gotten an amalgamation of the letters "K," "M," and "T" for each of their first names, with the Ozark star adding it to his forearm and Kaley opting to ink it on her wrist.
Matching tattoos aren't a new deal for the Emmy-nominated The Flight Attendant star, who has a "Boop" tattooed on her forearm as a nod to her close friend and co-star Zosia Mamet.
The symbolic ink comes not only exactly a month following Matilda's birth, born Matilda Carmine Richie Pelphrey on March 30, but a week following Kaley and Tom's one-year anniversary.
They each celebrated the milestone with a slew of photographs from their time together, having made their relationship official with a pair of social media posts as well last May.
The couple made their first red carpet appearance since becoming parents earlier in the week for the premiere of Tom's new series, Love & Death on HBO Max.
Kaley wore a bright blue Stella McCartney cape dress with a gold locket that bore the name of her daughter, while Tom was styled out in a sleek beige suit.
"Mommy and Daddy first night out," he captioned photos of the pair posing in front of the pool in their jaw-dropping mountain-lined backyard while holding their adorable newborn between them, receiving a host of gushing reactions from their followers.
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