Clowance was the third child and second daughter of Ross and Demelza Poldark. She was born at Nampara in 1794. Her mother had gone into labour suddenly and gave birth in no time, to the surprise of Ross, who returned home to find Demelza in bed.
Demelza had hidden Clowance under a sheet, as Ross potted around without knowing. When Ross asked Demelza whether she needed anything, Demelza told him that he could say hello to his daughter. Ross was delighted, and held and kissed his child. They later had a christening for her and celebrated their first christmas together.