Alfie Allen is best known for playing Theon Greyjoy in Game of Thrones

Lily Allen is an aunt!

The singer’s brother Alfie, best known for playing Theon Greyjoy on Game of Thrones, recently welcomed his first child with girlfriend Allie Teilz. The actor, 32, announced the baby news on Instagram Monday with a photo of the newborn adorably gripping his finger.

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“With full hearts and overwhelming joy @allieteilz and I introduce you to the newest member of our family,” Allen captioned the father-daughter photo. “She is perfect.”

Allie’s sister Mia also shared a photo of the couple’s child on Instagram. “Proud auntie moment my sweet libra niece + strong sister mama,” she said.

Neither Allen nor Teilz had previously announced a pregnancy before the arrival of their baby.

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The new parents were first romantically linked in June 2017 when they were spotted on a vacation together in Formentera, Spain.

Image zoom Jamie McCarthy/Getty

Allen’s famous friends, including Olivia Munn and Samantha Ronson, congratulated him on his bundle of joy in the comments section of his post.

Image zoom Lily and Alfie Allen Claire Greenway/Getty

The news of Allen’s child comes after his sister Lily recently opened about his embarrassing meeting with the late Princess Diana in her new memoir, My Thoughts Exactly.

The meeting came at the 1991 London premiere of Hear My Song, a film produced by Allen’s mother, where the kids were tasked with greeting Diana with gifts. “Diana the Princess of Wales came to the premiere. I was a flower girl and gave her a posy, Alfie had a box of handkerchiefs to give her but somehow he got his k— caught in his trouser zip moments before meeting her,” Allen recalled in her book, according to the Daily Mail.