It is thought that Lilley was entirely self-taught as an artist, studying in Paris regularly, including during the 1830 Revolution. He made sketches of these events which have since been lost. Lilley was also a great admirer of Dutch art and visited Holland. The Duke of Wellington sat for Lilley thirty-nine times, and he painted Prince Albert. He was a member of the Garrick Club and exhibited at the RA. He also made many informal portraits of his children and family. In 1891 Lilley moved to Sefton Park, Liverpool. He died at the age of 86. His grand-daughter remembered him fondly: 'My grandfather was a deeply religious man and one of the bst, his life was dedicated to refinement and beauty. As I lost both my parents when I was two years old I lived with my grandfather until his death...he was devoted to me and called me his little Queen. He was a learned man and was constantly quoting from the French authors, Plato, and other great men'.