PENNSYLVANIA (WLNS) – The holidays have come and gone, but one Pennsylvania mom has more reasons to keep celebrating.

Twins Millie and Mack are just four months old, but one day their mom will have a story to tell them.

Katie Robb Sewall always wanted to be a mother, but in 2014 – when she was just 27, she got a diagnosis she never expected: aggressive stage 3 breast cancer.

Her doctors at a Cleveland clinic focused on her whole health and preserving her fertility.

Dr. Halle Moore, Katie’s oncologist, said that chemotherapy drugs can damage ovaries and cause premature menopause for younger patients.

Katie had a double mastectomy. She and her husband decided to freeze some of her embryos before chemo.

After several rounds of chemo, Katie stayed on hormone therapy and in 2020 got the go-ahead to try and concieve.

After a couple attempts of IVF, the couple welcomed Mack and Millie.

“I feel really grateful to my oncologist for insisting that we not just rely on one form of fertility preservation… [becoming a mother] is a dream come true,” she said.