Woman delivers baby who is both daughter and niece

Families come in all different shapes and sizes these days, but one woman has become both mother and aunt to the baby girl she gave birth to last week.

Chapelle Cooper delivered the healthy newborn after agreeing to be a surrogate for her brother, Scott Stephenson, and his partner Michael Smith.

Named Harper Elizabeth Smith, Stephenson and Smith were delighted by their daughter's arrival 15 days early.

"This morning we welcomed the most amazing little lady to the world," Smith wrote on Facebook on the day of Harper's birth.

"We are blown away by the strength, heart and courage of Chapelle and will never be able to truly thank her for bringing us our perfect little bundle."

He and Stephenson had been keen to start a family but were nervous about surrogacy, worrying that they may not be able to find a suitable surrogate that they could trust to carry their child.

Having seen the stress her brother and Smith were going through, Cooper offered to become their surrogate and the three began working towards the exciting birth.

Cooper supplied her own egg while Smith offered his sperm to conceive the child, meaning Harper would be directly related to both of her dads and share some of Stephenson's characteristics through Cooper.

Posting about the birth on Facebook, Cooper thanked her brother and Smith for letting her be a part of the incredible process.

"They were amazing in the delivery room, they gave so much love and so much care to me and to Harper, cannot thank you enough," she wrote.

"Enjoy your new family life, I love you all so much.”

Though Cooper is Harper's biological mother, the little girl will be raised as Smith and Stephenson's daughter, only knowing Cooper as an aunt until she's old enough to understand how she was conceived.

The family plan to tell her the truth when she grows up, but until then Cooper intends to be a doting aunt.

“I don’t think I could’ve done it if I’d never seen her again,” she told Yahoo UK.