Question: Who is the mother of the Vintage Violence artist?

full_context: Document 1: Bramwell Booth: Born in Halifax, Yorkshire, England, the oldest child born to William Booth and Catherine Mumford, he had two brothers and five sisters, including Evangeline Booth, Catherine Booth-Clibborn, Emma Booth and Ballington Booth. The Booth family regularly moved from place to place as William Booth's ministry necessitated until the family finally settled in London in 1865. Bramwell Booth was involved in The Salvation Army right from its origins as the obscure Christian Mission, established in Whitechapel in 1865, into an international organisation with numerous and varied social activities. He was educated at home, briefly at a preparatory school and at the City of London School, where he was bullied.
Document 2: John Cale: John Davies Cale was born on 9 March 1942 in Garnant in the industrial Amman Valley of Wales to Will Cale, a coal miner, and Margaret Davies, a primary school teacher. Although his father spoke only English, his mother spoke and taught Welsh to Cale, which hindered his relationship with his father, although he began learning English at primary school, at around the age of seven. Cale was molested by two different men during his youth, an Anglican priest who molested him in a church and a music teacher.
Document 3: Ed Sheeran: Sheeran was born in Halifax, West Yorkshire on 17 February 1991. When he was a child, he moved with his family from Hebden Bridge to Framlingham in Suffolk. He has an older brother named Matthew who works as a composer. Sheeran's parents, John and Imogen, are from London. His paternal grandparents are Irish, and Sheeran has stated that his father is from a "very large" Catholic family. John is an art curator and lecturer, and Imogen is a culture publicist turned jewellery designer. His parents ran Sheeran Lock, an independent art consultancy, from 1990 to 2010.Sheeran sang in a local church choir from the age of four, learned to play the guitar during his time at Rishworth School, and began writing songs while at Thomas Mills High School in Framlingham. He was accepted at the National Youth Theatre in London as a teenager. He successfully auditioned for Youth Music Theatre UK in 2007 and joined their production of Frankenstein in Plymouth. He is a patron of Youth Music Theatre UK (now renamed British Youth Music Theatre) and of Access to Music, where he studied Artist Development. Sheeran is a second cousin of Northern Irish broadcaster Gordon Burns, who hosted the British game show The Krypton Factor.
Document 4: The Velvet Underground: The Velvet Underground was an American rock band formed in 1964 in New York City by singer/guitarist Lou Reed, multi-instrumentalist John Cale, guitarist Sterling Morrison, and drummer Angus MacLise (replaced by Moe Tucker in 1965). The band was initially active between 1965 and 1973, and was briefly managed by the pop artist Andy Warhol, serving as the house band at the Factory and Warhol's "Exploding Plastic Inevitable" events from 1966 to 1967. Their debut album, "The Velvet Underground & Nico" (with German-born singer and model Nico), was released in 1967 to critical indifference and poor sales but has become critically acclaimed; in 2003, "Rolling Stone" called it the "most prophetic rock album ever made."
Document 5: 23 Solo Pieces for La Naissance de L'Amour: 23 Solo Pieces for La Naissance de L'Amour is the soundtrack album by Welsh multi-instrumentalist and composer John Cale. It was released in November 1993 on Belgian independent label Les Disques du Crépuscule. It was produced by Cale's then collaborator Jean-Michel Reusser. It is the original music score for Philippe Garrel's film "La Naissance de l'amour".
Document 6: Live at Rockpalast (John Cale album): Live at Rockpalast is a two-disc live album by Welsh musician John Cale. It was released in October 2010 on German record label Made in Germany. It was recorded during his two shows for German music television show Rockpalast on 14 October 1984 at Grugahalle, Essen (first disc; with full band) and 6 March 1983 at Zeche, Bochum (second disc; Cale solo with guitar and piano). This concert is missing "Risé, Sam And Rimsky-Korsakov" (Cale, Shepard) narrated by his then-wife Risé Irushalmi.
Document 7: Idwal Robling: Robling was born in Ynyshir in the Rhondda Valley, where he attended the local grammar school. His education was interrupted by the Second World War, and upon being called up was accepted for service in the Royal Navy. However, he was selected by ballot to become a Bevin Boy so instead of going to the Navy he was conscripted to work in the coal mines. After the war, he resumed his education and qualified as a teacher after attending Caerleon College and Loughborough University, although instead of teaching he decided on a different career and became a manager at the Lovell's sweet factory in Newport, Monmouthshire.
Document 8: Animal Justice: Animal Justice is the first EP by Welsh musician John Cale. It was released in September 1977 by record label Illegal.
Document 9: Gwynfor Evans: Gwynfor Evans was born in Barry, near Cardiff, to Dan Evans and Catherine Richard. He had a brother named Alcwyn, and a sister named Ceridwen. His father ran a chain of shops in Barry, and his mother a china shop. His mother was a fluent Welsh speaker. As a boy, he was educated at Gladstone Road School. Later on he was educated at Barry County School, where he was captain of the school's cricket and hockey teams. At the school he began learning the Welsh language, but did not become fully fluent until the age of seventeen.
Document 10: If You Were Still Around: "If You Were Still Around" is a song by Welsh musician and composer John Cale. It was written by John Cale together with playwright Sam Shepard. It was originally released on Cale's 1982 album "Music for a New Society". On 27 October 2014, a year after the death of his The Velvet Underground–bandmate Lou Reed, Cale released a new version of this song. For this version was also released music video directed by Abigail Portner. At the beginning of the video Cale is lying on the floor in a fetal position and after he views the photos of Reed and other deceased people associated with the Velvet Underground and The Factory: Sterling Morrison, Nico, Andy Warhol, and Edie Sedgwick.
Document 11: Hywel Teifi Edwards: Born and raised in Aberarth, Ceredigion, Edwards attended Aberaeron Grammar School and the University College of Wales, Aberystwyth. He taught Welsh at Garw Grammar School, Pontycymmer, where he met his wife Aerona, before becoming an extramural lecturer in Welsh literature at University of Wales, Swansea, and later Professor and Head of the Welsh Department. He and his wife had two children, Huw Edwards and Meinir Edwards now Menir Krishnasamy. He retired from full-time teaching in 1995 but continued to lecture and write books. Edwards was the leading authority on the history of the National Eisteddfod of Wales.
Document 12: Process (John Cale album): Process is the soundtrack album by Welsh multi-instrumentalist and composer John Cale. It was released in August 2005 on French independent label Syntax Records. It was produced, composed and performed by John Cale. It is the original music score for C.S. Leigh's film "Process". It was primarily released on CD and three tracks from album ("Suicide Theme", "Candles" and "Reading Poem") was also released on limited 10" vinyl album.
Document 13: Roger Waters: Waters was born on 6 September 1943, the younger of two boys, to Mary (née Whyte; 1913–2009) and Eric Fletcher Waters (1914–1944), in Great Bookham, Surrey. His father, the son of a coal miner and Labour Party activist, was a schoolteacher, a devout Christian, and a Communist Party member. In the early years of the Second World War, Waters' father was a conscientious objector who drove an ambulance during the Blitz.
Document 14: Vintage Violence: Vintage Violence is the debut solo studio album by Welsh musician John Cale, released on 25 March 1970 by Columbia Records. Cale and Lewis Merenstein produced the album.
Document 15: Kenton Cool: Cool was born in Slough, Berkshire in 1973. His family surname was originally Kuhle and was changed during the Second World War by his half-German grandfather. His father was a photographer and his mother a florist, and the family home was near to Uxbridge, in Middlesex. He was schooled at John Hampden Grammar School in High Wycombe, and later obtained a place at the University of Leeds. Kenton Cool graduated from the University of Leeds in 1994 after studying BSc Geological Sciences.
ground_truth: Margaret Davies
sub_queries: Who made Vintage Violence? Answer: John Cale
Who is the mother of John Cale ? Answer: Margaret Davies