Hailee Steinfeld shared in her Beau Society newsletter that she and husband Josh Allen named their newborn daughter Harper Haize, alongside a handwritten letter to the baby that captures the shock, joy, and exhaustion of the first weeks of motherhood.
Hailee Steinfeld finally let the name out.
In the latest edition of her Beau Society newsletter, released Friday, June 19, the 29-year-old Sinners actress revealed that she and husband Josh Allen — the Buffalo Bills quarterback — named their baby girl Harper Haize.
Steinfeld also paired the announcement with a letter she wrote to her daughter, beginning, “Dearest Harper,” and opening up about the strange, powerful way a newborn can instantly feel both real and impossible.
“I’m in awe of you,” she wrote. “You’ve been here for only a short while now, and somehow it feels as though you’ve always been ours.”
The letter moves through the quiet specifics of early motherhood: the exhaustion mixed with awe, the late-night moments where time stops making sense, and the everyday measurements that replace everything before—“in ounces, naps missed and naps miraculously taken, in diaper changes.”
Steinfeld described looking at her baby as she slept on her chest and still wondering how this new life could be so present. She also shared the little household realities that come with having a daughter. including the way Allen is “officially outnumbered” when it comes to choosing a movie for movie night.
“You daddy and I look at you often and ask each other the same question: How did we get so lucky to have you?” she wrote.
She added that people told her “not to blink. ” and that she understands why now—because even in a matter of weeks she’s already missing versions of her daughter that still feel like yesterday. She wrote about the baby’s tiny fingers wrapping around hers. the “impossibly small diapers. ” and the way the smallest details carry a kind of permanence in the mind.
As the weeks have settled in, Steinfeld said she’s learning what motherhood actually changes. “People tell you becoming a mother changes everything,” she wrote, “but no one tells you how, why, or when exactly.”
Instead of focusing only on the big moments, she framed it as a daily transformation—“allowing yourself to become someone new over and over again”—with a softer, stronger, more patient version of herself showing up each day.
The letter ends with an address that lands right on the stakes of the relationship: “And even though I know I am meant to guide you through this life… Harper Haize Allen, the truth is that already, you have taught me far more than I could ever teach you.”
Her “Love, Your mom” signature closes a note that reads like a private vow made public.
Allen and Steinfeld announced the birth of their first child in early April. Their baby’s name is Harper Haize, as revealed in Steinfeld’s Beau Society newsletter on June 19.
Steinfeld and Allen began dating in May 2023 and married on May 31, 2025. They announced her pregnancy in October 2025.
In another recent newsletter, Steinfeld also opened up about her postpartum journey and how she’s staying healthy after giving birth. She has additionally shared photos celebrating her first Mother’s Day.
Hailee Steinfeld Josh Allen Beau Society newsletter Harper Haize celebrity babies Sinners actress postpartum journey newborn daughter