Question: Who is the sister of the Sugar Mountain performer?

full_context: Document 1: Scott Young (writer): Scott Alexander Young (April 14, 1918 – June 12, 2005) was a Canadian journalist, sportswriter, novelist and the father of musicians Neil Young and Astrid Young. Over his career, Young wrote 45 books, including novels and non-fiction for adult and youth audiences.
Document 2: You Gave Me a Mountain: ``You Gave Me a Mountain ''(sometimes credited as`` Lord, You Gave Me a Mountain'') is a song written by country singer - songwriter Marty Robbins during the 1960s. It has been recorded by many artists, including Robbins himself, but the highest - charting version of the song was by Frankie Laine in 1969. This version was included on Laine's album of the same name.
Document 3: Nick Sagan: Nick Sagan (born September 16, 1970 in Boston, Massachusetts) is an American novelist and screenwriter. He is the author of the science fiction novels "Idlewild", "Edenborn", and "Everfree", and his screen credits include episodes of "" and "". He is the son of astronomer Carl Sagan and artist and writer Linda Salzman.
Document 4: Old Man from the Mountain: "Old Man from the Mountain" is a song written and recorded by American country music artist Merle Haggard and The Strangers. It was released in June 1974 as the second single from the album "Merle Haggard Presents His 30th Album". It was Haggard and The Strangers eighteenth number one on the country singles chart. The single went to number one for a single week and spent a total of ten weeks on the chart.
Document 5: Hank Snow: Snow moved to Nashville, Tennessee, in 1949, and "Hank Snow, the Singing Ranger" (modified from his earlier nickname, the Yodeling Ranger), began recording for RCA Victor in the United States in 1949. His first release in the United States, "Marriage Vow" climbed to number ten on the country charts in the fall of 1949; However, it wasn't until he was invited to play at the Grand Ole Opry in 1950 that he gained serious significance in the United States. His second release in early 1950, "I'm Moving On" was the first of seven number 1 hits on the country charts. "I'm Moving On" stayed at the top for 21 weeks, setting the all-time record for most weeks at number 1.
Document 6: Cowgirl in the Sand: "Cowgirl in the Sand" is a song written by Neil Young and first released on his 1969 album "Everybody Knows This Is Nowhere". Young has also included the live versions of the song on several albums and on the Crosby, Stills, Nash and Young album "4 Way Street". It has also been covered by The Byrds on their self-titled album. Like two other songs from "Everybody Knows This Is Nowhere", "Cinnamon Girl" and "Down by the River", Young wrote "Cowgirl in the Sand" while he was suffering from the flu with a high fever at his home in Topanga, California.
Document 7: John Walter Scott: John Walter Scott (November 2, 1845 – January 4, 1919) of New York City, was originally from England, but he emigrated to the United States to take part in the California Gold Rush. Unsuccessful at the prospecting trade, Scott began to sell postage stamps for collectors and in a short period of time became the nation's leading stamp dealer. During his lifetime, he was known as "The Father of American Philately" by his fellow stamp collectors.
Document 8: William Young (Nova Scotia politician): Born in Falkirk, the son of John Young and Agnes Renny, Young was first elected to the Nova Scotia House of Assembly in 1836 as a Reformer (or Liberal) and, as a lawyer, defended Reform journalists accused of libel. When responsible government was instituted in 1848, Young hoped to become the first Premier but was passed over in favour of fellow reformer James Boyle Uniacke and Young became Speaker. However, Young succeeded Uniacke in 1854.
Document 9: James Young (Upper Canada politician): He was born in Nova Scotia in 1777 and settled in Ameliasburgh Township in Upper Canada. In 1808, he was named justice of the peace in the Midland District. He served in the local militia during the War of 1812 and became lieutenant colonel in 1824. He represented Hastings & Ameliasburg in the 6th Parliament of Upper Canada. He died at Carrying Place in 1831.
Document 10: The Loner (Neil Young song): "The Loner" is a song by Neil Young, his first solo single. It was released on his solo debut album in November 1968, and then an edited version as his debut solo single three months later on Reprise Records. It missed the "Billboard" Hot 100 chart completely, but over time has become a staple of his performance repertoire. Both it and "Sugar Mountain", its B-side recorded live at the Canterbury House in Ann Arbor, Michigan, were released on album together for his 1977 compilation, "Decade".
Document 11: Sugar Mountain (song): "Sugar Mountain" is a song by Canadian folk rock singer and composer Neil Young. Young composed the song on November 12, 1964—his 19th birthday—at the Victoria Hotel in Fort William, Ontario (now Thunder Bay), where he had been touring with his Winnipeg band the Squires. Its lyrics are reminiscences about his youth in Winnipeg, Manitoba.
Document 12: William T. Young: William T. Young attended the University of Kentucky where he was a member of the Sigma Alpha Epsilon fraternity. Young graduated with high distinction in 1939 with a Bachelor of Science in mechanical engineering. After a short employment with Bailey Meter in Cleveland, Ohio, he served as a captain in the United States Army from 1941 to 1945.
Document 13: Jock Young: Jock Young was educated at the London School of Economics. His PhD was an ethnography of drug use in Notting Hill, West London, out of which he developed the concept of moral panic. The research was published as "The Drugtakers". He was a founding member of the National Deviancy Conferences and a group of critical criminologists in which milieu he wrote the groundbreaking, "The New Criminology: For a Social Theory of Deviance" in 1973, with Ian Taylor and Paul Walton and "The Manufacture of News" (with Stan Cohen).
Document 14: Old Man (song): ``Old Man ''is a song written and performed by Neil Young on his 1972 album Harvest.`` Old Man'' was released as a single on Reprise Records in the spring of 1972, and reached # 31 on the Billboard Hot 100 singles chart for the week ending June 3.
Document 15: Jacob Richler: Jacob Richler is a Canadian newspaper and magazine journalist, and the son of novelist Mordecai Richler and Florence Isabel (Wood). He was the inspiration for his father's "Jacob Two-Two" trilogy of children's books.
ground_truth: Astrid Young
sub_queries: Sugar Mountain >> performer Answer: Neil Young
Neil Young >> sibling Answer: Astrid Young