Terminally ill author, who wrote a dating profile for her husband, dies aged 51.

The children’s book author who penned a heartbreaking love letter to her husband in the form of a ‘dating profile’ has died.

Amy Krouse Rosenthal passed away at age 51 from ovarian cancer, her agent confirmed to PEOPLE magazine.

"Everything Amy did was life and love affirming," her agent and friend Amy Rennert said in a statement.

"She was such a bright light with a great sense of wonder. Amy loved her family. She loved words, ideas, connections.

"She taught us that life's seemingly small moments are not really small at all. Amy's final essay, written under the most difficult of circumstances - a love letter to her husband Jason - was the ultimate gift to him and also to the rest of us."

Amy - who had written over 20 books for children - was diagnosed with ovarian cancer in 2015, and made headlines all over the world after she wrote a heartfelt essay for the husband she knew she was leaving behind.

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In the article for the New York Times, titled 'You May Want To Marry My Husband', Amy told the story of how she fell in love with her husband, Jason, in just one day.

"He is an easy man to fall in love with. I did it in one day," she wrote.

"I have never been on Tinder, Bumble or eHarmony, but I’m going to create a general profile for Jason right here, based on my experience of coexisting in the same house with him for, like, 9490 days."

She wrote about his cooking skills, among other talents, and described him as "an absolutely wonderful father" to their sons Justin, Miles and daughter, Paris.

A week later, Jason responded to his wife's emotional essay, saying, "It is Amy’s gift with words that has drawn the universe in."

Fellow authors have begun to pay tribute to Amy online after hearing the news of her death.

My friend Amy Krouse Rosenthal has died. She was a brilliant writer, and an even better friend. Amy's genius was in her generosity...

— John Green (@johngreen) March 13, 2017

...she found ways to be kind to readers, to give them surprises and joy. No one wrote like Amy. No one saw the world the way she did.

— John Green (@johngreen) March 13, 2017