The mother of a cancer patient has become the first woman to give birth at London's world famous Great Ormond Street children's hospital.

The 157-year-old hospital treats sick babies and children but does not have a maternity unit, and there are no records of children ever having been born there.

Baby Zac decided to arrive while his mother Nicola Tyler, 32, was staying with her six-year-old daughter Kelly, who is having treatment for Non-Hodgkin's Lymphoma there.

Four days after Tyler arrived at the hospital – she went in labor.

"I went and took a warm bath and lay on the bed in Kelly's room,” she said. “But within a matter of minutes my contractions had become stronger and more frequent.”

Staff nurse Caroline Kanyanga delivered Zac with the help of several other health care workers as the paramedics made their way to the children’s hospital.

Kelly was diagnosed with Non-Hodgkin's Lymphoma in her neck in June and is making steady progress.

After her baby brother was born, Tyler said her daughter was all smiles.

"She was really pleased... calling all the nurses in, saying 'come and see my brother'."

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