One mom's pregnancy joy led to a valiant cancer battle, and left a legacy of love

When Kimberly Castelli — a 39-year-old Catholic wife, mother of three girls, and school nurse — discovered she was unexpectedly pregnant with her fourth child, she could not have imagined that the tiny life within her would soon reveal her own life-altering diagnosis.

What followed was a story of bravery, steadfast faith, and maternal love that embraced both the sanctity of life and the reality of suffering.

An unexpected blessing 

After returning from a family vacation to Portugal and Spain in the summer of 2024, Kim and her husband Brian discovered she was pregnant. The couple hadn’t been planning for another baby, and had even given away all their baby items, so the unexpected news felt almost miraculous.

“She couldn’t believe it,” her sister, Gabrielle Avila, told Live Action News.

Kim later detailed learning the news in a series of private Instagram posts from 2025. “It came as a surprise for many reasons but we were so excited for this little gift,” she wrote. “I still can remember hearing and seeing the baby’s heartbeat at my first check up. I immediately fell in love with this little one, and in my heart I knew God had a plan for this baby and our family. He or she was meant to be here.”

But the joy the family felt turned to worry when early prenatal testing brought alarming news.

Test results lead to an alarming diagnosis

Kim’s non-invasive prenatal test (NIPT), a simple blood test, returned abnormal results showing “multiple aneuploidy” and unexplained circulating DNA. At first, the results were confusing. Her OB/GYN suggested she ignore the results, but something didn’t sit right. She sought the advice of the OB/GYN who had delivered her other three children, but who had since retired; he suggested she look into it further.

“He kept saying, ‘I just really feel like something else is going on here,’” Avila told Live Action News.

A redraw produced the same result. Eventually, Kim was referred to a National Institutes of Health (NIH) study examining women with similar NIPT results, which showed that women with such findings sometimes have cancer.

A full-body MRI, performed while she was pregnant, revealed the devastating news: Stage 4 colon cancer which had spread to her liver, involved other lymph nodes, and also showed some activity in her lungs. Until then, Kim had no symptoms.

“She was an active school nurse. She was out with her kids all the time,” Avila said, noting that Kim had only experienced nausea, which she chalked up to being pregnant. “She didn’t really think anything of it.”

A resolution to save her baby

The diagnosis struck an especially deep wound. Kim’s own mother had died of cancer when Kim was just six years old, which had a devastating impact on her life.

“This was always her biggest fear,” her sister said. “Getting sick and leaving the girls.”

Yet from the beginning, Kim was resolute about one thing. When doctors asked about her “intentions” for the pregnancy, subtly raising the possibility of abortion, her response was unwavering.

“She always said that this baby was her miracle baby,” her sister recalled. “She said [baby] Catherine saved her in so many ways. There was no way any harm was coming to this baby.”

Avila noted that though Kim had been raised Catholic, she had at one time been more ambivalent about the pro-life position. Then, as a young nurse, Kim had been required during hospital training to reassemble the pieces of an aborted child — a task necessary after a surgical abortion to ensure that no body parts are left behind.

“That totally changed her forever,” Avila said, noting that the horrifying experience, as well as becoming a mother herself, cemented Kim’s pro-life views.

In order to protect her preborn baby, Kim refused invasive prenatal testing like amniocentesis, knowing that it had a higher risk of causing miscarriage. She eventually found a Christian OB/GYN who prayed with her during appointments and reassured her that he had never participated in abortion.

After learning of her cancer diagnosis at 20 weeks pregnant, Kim began receiving chemotherapy treatments, which were deemed safe for her preborn daughter, under careful monitoring.

Kim and Brian's baby girl, whom they named Catherine Gianna (after St. Catherine of Siena and St. Gianna Beretta Molla), was born early (and healthy) at 35 weeks in February 2025. Kim and her family had been praying through St. Gianna’s intercession, drawing strength from the saint who chose her child’s life over her own.

“They didn’t even know if it was a boy or girl until birth,” Kim's sister said. “But they knew Gianna had to be part of her name.”

Navigating a diagnosis with faith

Though navigating the cancer diagnosis while raising young daughters was challenging and frightening, Kim’s faith never wavered.

Her treatment continued after Catherine's birth — and for a time, it seemed to be working. In early August, doctors told Kim the tumors were shrinking. “They took away one of the chemotherapy drugs because her response was so good,” her sister recalled.

But weeks later, new scans revealed aggressive progression. Despite the disappointing change, Kim remained hopeful until the end.

Avila said that during her sister's treatment and time in hospice she often lay under a blanket, saying, “Jesus, I surrender; take care of everything.”

Throughout it all, Kim clung to her faith, gratitude, and hope.

The heart of a mother

As her condition declined, Kim’s motherhood remained visible in the smallest details, as she continued to pour her attention and love into raising her daughters — 10-year-old Olivia, seven-year-old Juliette, four-year-old Diana, and baby Catherine. She continued family traditions, even while facing life-altering news. Just days before traveling to the NIH, she even hosted her annual All Saints Day party, decorating the house and dressing as St. Gianna herself.

“She didn’t want to make a big deal of [her cancer diagnosis]” her sister said. “She always put the girls first.”

Avila accompanied Kim to one of her later appointments, and Avila had brought her nursing son. Because of the infant's presence, Avila almost wasn’t allowed into the appointment with Kim. 

Avila recalled to Live Action News:

“I was arguing with receptionists, upset I had brought him. Behind me, Aunt Kimmie just picked him up, even though she was so weak, and crying, said, ‘There has to be a better way for moms and babies in this world. It isn’t right. I wish Catherine could have come to my treatments.”

She was in total mom mode. That’s who she was, always trying to make it easier and better for other moms, even when we were out.

If she could hold a door, give up a seat, or do anything to support another mom, she would. Her identity as mother was lived out during her final days on Earth and still is in the next life. It was never the medication, diets, or supplements that kept her alive as long as she lived with that diagnosis. It was her love for her girls.” 

Kim passed from this life to the next, surrounded by prayer, on December 10, 2025.

At the time of Kim's death, baby Catherine was 10 months old. Her family believes that without the unexpected blessing of pregnancy, Kim may not have known she had cancer until there were no treatment options available to her. The diagnosis gave Kim the opportunity to surrender to God and prepare for whatever lay ahead, while cherishing every moment with her husband and her young daughters.

Kimberly Castelli’s story is not only one of suffering, but of meaning. In life and in death, she bore witness to the fact that love is worth the cost, that motherhood is a vocation without limits, and that even in the darkest moments, God remains present.

As she often said during her illness, “Jesus is the best medicine.”