Princess Martha Louise of Norway's Daughter Celebrates First Birthday Since Death of Father Ari Behn

Princess Märtha Louise of Norway’s daughter is marking her first birthday celebration without her father Ari Behn.

On Thursday, the princess, 48, uploaded a series of Instagram photos to wish her middle child Leah Isadora a happy 15th birthday, acknowledging the celebration is particularly “bittersweet,” as it is the first birthday since her ex-husband and the father of her three daughters Ari Behn died by suicide on Christmas Day.

“Happy 15th Birthday, my wonderful Leah. You are an amazing young woman with so many talents; you are funny, kind, beautiful and graceful with a smart head on your shoulders,” Märtha Louise captioned the post. “You are definitely the most organized person in the family — for which I am eternally grateful — and you have the gift of art from your dad that expresses itself through beautiful makeup IG posts.”

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Martha Louise/Instagram Leah Isadora

Martha Louise/Instagram Leah Isadora

It continued, “And although this day is bittersweet in more ways than one, you make the best of it and stay true to your emotions. You keep inspiring me every day, darling. I am so proud of you. Love you with all my heart.”

Märtha Louise, who is now dating American “spiritual guide” to the stars Shaman Durek, was married to Behn for 15 years before separating in 2016 and officially divorcing in 2017. The late writer was also father to daughters 16-year-old Maud Angelica and 11-year-old Emma Tallulah.

A statement from the Royal House of Norway at the time of their split said the separation was amicable, and that the two would continue to co-parent their three kids.

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JONATHAN NACKSTRAND/AFP/Getty Princess Märtha Louise and Ari Behn

“We are human,” Princess Märtha Louise said in the statement, adding the couple had tried “everything in their power to make the marriage work.”

She added: “The marriage is over, but we stand together as parents.”

In early January, the princess opened up about the recent death of Behn, when the royal family laid Behn to rest on Jan. 3 at Oslo Cathedral. Hours after the ceremony Märtha Louise broke her silence on her former husband, who was 47 at the time of his death.

“Dear Ari, We were supposed to be together at Christmas and celebrating. We had all been looking forward to it. And we are so infinitely sad and sorry for the loss of just you, because you were the girls’ warm, funny, wise and good dad that they so dearly miss,” the royal wrote on Instagram, along with a photo of her late ex.

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Mark Cuthbert/UK Press via Getty Princess Märtha Louise, Ari Behn and their three daughters Maud Angelica, Leah Isadora and Emma Tallulah in 2013

“We miss the funny comments, your fine viewpoints, the poetic tone, the overflowing compliments, the great love you had for them. Today you would have been so proud of them. But now there is a void where you were, because no one can ever replace you for our beautiful girls. And it is so painful to think that you would leave the earth. We are in deep sorrow and pain all together,” she said. “An invisible illness took you more and more, because that’s when the mental health fails. For a long time, we gradually saw you disappear, but we held on to the belief that this would go well. Your family fought for you. They have been there for you day and night.”

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The mom of three concluded, “You are and will continue to be deeply missed, Ari. And I feel sad that you never really understood how loved you were. I hope that we who are left can be good at praising each other and saying the nice words to each other. For we have this life to share just how happy we are for each other and what wonderful qualities we see in each other. We keep you in love, Ari, and move on with your words: Every day is a party and you are a piece of jewelry.”