"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, Debra Donovan, wrote Thursday morning on the Facebook page chronicling the couple's lung transplant journey.
Katie was in hospice care in her Flemingsburg, Kentucky, home since Sept. 7. Her husband, Dalton died just days earlier on Saturday after suffering from the same disease. He was 25 years old.
The couple met online and married in 2011. They both had lung transplants, but neither of the transplants were successful for long.
Dalton moved back to Missouri after a lung transplant in 2014, so his parents could care for him.
Katie received a lung transplant last year and then developed lymphoma and had kidney failure. She was in hospice care in Flemingsburg, Kentucky when her husband died.
The couple used FaceTime to talk last weekend as Dalton was dying, Donovan told CNN.
"She told him that she loved him," Donovan said. "We don't know if he heard her."
The young couple garnered worldwide attention last year after CNN wrote about Katie's fight to get a lung transplant.
They were known as the real "Fault in Our Stars" couple, as their love story bore a resemblance to the 2012 book and 2014 movie "The Fault in Our Stars," in which teenage cancer patients fall in love.