'Fault in Our Stars' Couple Die Days Apart From Each Other: 'They Are Now United'

(INSIDE EDITION) The young married couple whose love story read like a real-life version of The Fault in Our Stars have lost their respective battles with cystic fibrosis just days apart from each other, family said.

Katie and Dalton Prager met online when they were both 18, bonding over their shared experiences fighting the terminal lung disease.

They fell in love and met despite the potential for Katie, of Kentucky, to contract Missouri-based Dalton's dangerous and contagious infection called Burkholderia cepacia. They were married in 2011 when they were both 20.

Katie eventually contracted the infection and though the pair received new lungs, the transplants were ultimately unsuccessful.

The couple were apart as they received treatment in separate states and though plans were made to reunite them, Dalton passed away before that could happen.

Dalton died in a hospital bed in St. Louis as Katie watched on FaceTime. He was 25.

"My angel, my best friend, the love of my life, my husband went to be with the Lord our God today. Dalton fought a long hard battle with Cystic Fibrosis," she wrote on Facebook on September 17. "He was a courageous fighter and 'give up' wasn't in his vocabulary. Thank you for all of your love, prayers and kind words that you have shown to us over the past few years. God bless each of you."

His funeral was Wednesday.

A day later, Katie lost her own battle. She was 26.

"Early this morning, she gained her wish of being at home, in her bed, surrounded by her mom, dad, brother and her dogs, dying peacefully, away from the hospital, tubes, IVs. I know Dalton was waiting with open arms," Katie's mother wrote on Facebook.

Dalton's mother echoed her sentiments, writing: "I truly believe Dalton had prepared a place for his wife."

Visitation and funeral arrangements for Katie are pending.

Their story touched countless others, many of whom took to social media to mourn the inspiring pair.

"They are now united and can breathe without the help of machines. Praying for their families to find comfort in the coming days," one person posted on their shared Facebook page.

"Thank you [for] sharing their story with the world," another person wrote. "They have both left a legacy that we will never forget."