Hello Heather,
Henry Yorke Sparks was born in Montevideo in 1845 to Sarah (nee Waterworth) Henry Palafox Gerona's second wife. His first wife died in childbirth in 1841 in Montevideo but the child Overton survived. There were three boys born before the family fled Montevideo in 1852.
Any further information please ask...best wishes John Sparks