Definition: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Input: Passage: George Frederic Watts was born in 1817, the son of a London musical instrument manufacturer. His two brothers died in 1823, and his mother in 1826, giving Watts an obsession with death throughout his life. Watts was apprenticed as a sculptor at the age of 10, and by his mid-teens was proficient enough as an artist to be earning a living as a portrait painter. At the age of 18 he gained admission to the Royal Academy schools, although he disliked their methods and his attendance was intermittent. From 1837, Watts was successful enough to devote himself full-time to painting.In 1843 Watts travelled to Italy where he remained for four years. On his return to London he suffered from melancholia, and painted many notably gloomy works. His skills were widely celebrated, and in 1856 he decided to devote himself to portrait painting. His portraits were extremely highly regarded, and in 1867 he was elected to the Royal Academy, at the time the highest honour available to an artist, although he rapidly became disillusioned with its culture. From 1870 onwards he became widely renowned as a painter of allegorical and mythical subjects; by this time, he was one of the most highly regarded artists in the world. In 1881 he added a glass-roofed gallery to his home at Little Holland House, which was open to the public at weekends, further increasing his fame.
Output:
What is the last name of the person whose two brothers died in 1823?