After cancer took away her twin sister’s ability to carry a second baby, Dawn Policastro jumped in to help and became sister Allison’s surrogate.

Recently, Dawn gave birth to her nephew this August 5th.

Professional photographer Allison Rose‘s  photos of the sisters during Dawn’s pregnancy went viral this week.

“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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