After finding out her identical twin sister was unable to have a baby, a Long Island, New York, woman offered to carry her sister’s baby. On Wednesday, August 5, she gave birth to a healthy baby boy, who will be referred to as her nephew, Patch.com reported.

In 2009, Allison Ardolino Dinkelacker was 30 weeks pregnant with her first child when she learned she had stage 3 breast cancer. She needed to start chemotherapy immediately, and her son Dylan was born by emergency caesarean section at 31 weeks.

Cancer-free but unable to conceive again because her cancer was brought on by hormones, Allison wanted another child to grow her family. Her twin sister, Dawn Ardolino Policastro, came with her to a doctor’s appointment, where they were told that were Allison to survive a pregnancy, she’d be unable to carry another child.

“Well before he (the doctor) even finished his sentence, Dawn jumped in and said, ‘It doesn’t matter because I am going to carry their child,’” Allison wrote on her Facebook page.

Dawn gave birth to her nephew, Hudson, on August 5. A professional photographer’s photos of the sisters during Dawn’s pregnancy went viral, and had received over 69,000 likes and over 12,000 shares as of Tuesday morning.

“How can we begin to thank you for the tremendous generosity and sacrifice you have so willingly bestowed these last few months?” Allison wrote on her Facebook page.

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