More than a year after Sam Tripson lost his battle with lymphatic cancer, his wife, Kristen, welcomed the couple's third child thanks to in vitro fertilization.

Lillian Belle Tripson was born Sunday morning.

"Everyone is doing well and happy to be settling in back at home," Tripson wrote in an Instagram post announcing the birth.

Lillian is Sam and Kristen Tripson's third child together and their second since the couple underwent in vitro fertilization procedures in the face of Sam Tripson's cancer diagnosis.

Sam Tripson died in September 2015, four years after he was first diagnosed with non-Hodgkin's lymphoma and a month after the cancer, which had been in remission, returned.

Kristen Tripson took to Instagram to detail her family's struggles as Sam Tripson went to treatment and later, as she coped with her loss.

"Sam's decline was so fierce and so rapid that I didn't even see it happening," Tripson wrote in September. "But looking back, it was obvious. He was dying. Did he know? Even if his mind wasn't able to process the thought, deep in his soul, he must have known.

"Lord, I miss him. So very much. That goes without saying. But you can't watch someone you love so deeply suffer so much without feeling a little relief when their pain is gone."

She announced in April that she was expecting her third child "and yes," she wrote, "it's Sam's."

The couple froze four embryos to give them the chance to have more biological children despite Sam Tripson's cancer treatments.

"Though we never talked much about 'the end,' we did talk about our embryos," Kristen Tripson wrote. "I know it's a very personal, private subject, but to us, they were our potential children. On ice. It was always our plan, regardless of what happened, that they would have a chance at life."

One embryo became the couple's daughter, Alice Ann. Another was lost the summer before Sam Tripson's death.

"Over the past 6 months, there has never been a doubt as to what I was going to do," she wrote. "Even in the ICU during his final hours, I knew what I was going to do. After he was gone, I laid next to him for a long time. I prayed for the strength I would need to get up and leave the hospital and eventually, when I was ready, to move forward with our plans."

In February, Kristen Tripson had both the remaining embryos transferred to her, and one survived.

"The way I see it, I get one and Sam gets one," she wrote. "Of course, it's bittersweet. And yes, a bit unconventional. But it was our decision and what I consider to be one of life's most beautiful blessings."