“Game of Thrones”' Hafþór Júlíus Björnsson and Wife Kelsey Share Emotional Post 1 Year After Losing Baby Girl at 21 Weeks

"So many firsts that we will be missing for the entirety of our lives," they wrote

Hafþór Júlíus Björnsson and his wife Kelsey are taking a moment to reflect on a year without their daughter.

On Friday, Nov. 8, the actor, who played The Mountain on Game of Thrones, and his wife shared a joint post on Instagram as they reflected on the one year anniversary of the death of their baby girl Grace, whom they lost at 21 weeks.

"One year. 365 days have passed since your day of birth. 366 days have passed since we learned of your death in my womb. One year, 365 days, without you here, with us," the couple wrote in a lengthy Instagram caption.

"You didn’t get to feel the comfort of my arms or breast. You didn’t get to look up and see my face or your daddy’s face. We didn’t get to see your first smile, your first tooth, your first giggle. We didn’t get to clap and cheer when you first sat up or pulled yourself to stand. So many firsts that we will be missing for the entirety of our lives."

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Related: Game of Thrones' Hafþór Júlíus Björnsson and Wife Kelsey Henson Lose Baby Girl at 21 Weeks: 'Great Sorrow'

They went on to say that the death of their baby daughter was something they hadn't considered would ever happen, but that posting and talking about her brings awareness to how often miscarriages happen.

"At the end of this life, we all die, some die earlier than others, some die before they get to take their first breath," they wrote. "For many of us we get to experience this death and grief first hand, many many years before it’s our time. Death is the one sure thing, yet something that so many fear."

"I invite you today to share this post to your story for my daughter’s birthday, helping to reduce the stigma of miscarriage/late miscarriage/still birth/tmfr/and infant death."

Related: Celebrities Who Have Shared Their Miscarriage Stories, in the Hopes of Helping Others

Last November, the couple, who also share 4-year-old son Stormur, shared on Instagram that they'd experienced a pregnancy loss, sharing photos of their brief time with their baby daughter and explaining the circumstances in a lengthy post.

"It is with great sorrow that we announce the birth of our daughter, Grace Morgan Hafthorsdottir, born Nov 8th at 21 1/2 weeks gestation. After a noticeable decrease in movement we found out her heart had stopped beating," they wrote.

"Words cannot describe our pain of this loss or our happiness at being able to spend time with our daughter. She is absolutely beautiful, with blonde lashes and brows and a little smile for mom and dad. The love we feel for her is overwhelming," the caption continued.

"The grief we feel will be with us forever but so will the love. All of our hopes and dreams for her have been taken away from us but I know I will be with her again. Her spirit lives on through us and her siblings. We ask that you respect our privacy at this time as we grieve this unbearable loss. Thank you all for any kind words and support."