Woman Gives Birth to Her Identical Twin Sister's Baby in Incredible Show of Love

It's the ultimate act of sisterly love: a woman carrying her identical sister's baby after a cancer diagnosis meant she was unable to.

It's the ultimate act of sisterly love: a woman carrying her identical twin's baby after she survived cancer.

Dawn Ardolino Policastro, from Long Island, New York, gave birth to her sister's son, Hudson, last week.

Photographer Allison Rose shared stunning photos of the two sisters posing together before Hudson's birth.

In 2009, Dawn's twin, Allison Ardolino Dinkelacker, was 30 weeks pregnant with her first son, Dylan, when she was diagnosed with Stage 3 breast cancer. Doctors said she needed to undergo chemotherapy immediately.

She delivered the healthy baby boy by C-section just a week later, on her - and her sister's - 33rd birthday.

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After months of chemotherapy and surgeries, she is now cancer free. But Allison knew she could not get pregnant again because the cancer had been brought on by hormones. Yet she desperately wanted another child.

That's when her sister stepped in.

During a visit to the doctor, "Dawn jumped in and said, ‘It doesn’t matter because I am going to carry their child,’” Allison wrote on Facebook.

She carried her sister's baby boy and gave birth to him on August 5.

Allison posted a thank you note to her sister online.

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

“You have given us not just the fulfillment of a wish we’ve had for the last six years, but a whole new life, and a family of four we thought we’d never have.”

She added: ''We have always seen it as we are one soul in two different bodies."

As photographer Allison Rose shared photos of the women, she shared their special story.

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"I am so honored to be able to share this amazing story of sisterhood, friendship, love and miracles," she wrote alongside the photographs. "Her selfless act of love and devotion has finally made their dreams come true!"

In one of their photos, they hold up a sign saying "My bun... her oven" with corresponding arrows.

Dawn has two of her own sons, seven-year-old Jake and three-year-old Ashton. Allison's son Dylan is now six.

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