William's great-grandfather, Edward Osler, was variously described as either a merchant seaman or a pirate. One of William's uncles (Edward Osler (1798–1863)), a medical officer in the Royal Navy, wrote the Life of Lord Exmouth and the poem The Voyage. (Osler, Edward, 1798–1863. The Voyage : a poem, written at sea, and in the West Indies, and illustrated by papers on natural history. London : Longman, 1830). william Osler's father, Featherstone Lake Osler (1805–1895), the son of a shipowner at Falmouth, Cornwall, was a former Lieutenant in the Royal Navy who served on HMS Victory. In 1831 Featherstone Osler was invited to serve on HMS Beagle as the science officer on Charles Darwin's historic voyage to the Galápagos Islands, but he turned it down because his father was dying. In 1833, Featherstone Osler announced he wanted to become a minister of the Church of England.