On 25 June 2006, while at home from Goldsmiths College, University of London, Aaron was practising with his air rifle, not realising his mother was close by. A 4.5 mm (.177 calibre) air gun pellet accidentally hit Jill in the neck, severing an artery and causing irreversible brain damage from hypoxia, leaving only her lower brain functions and no chance for recovery. She was taken to the Royal Berkshire Hospital intensive care unit where her condition was described as "critical but stable". Communication from ZTT Records confirmed on 1 September 2006 that Jill was in a natural coma and had been moved to a rehabilitation centre. In September 2009, Horn told "The Times" confirmed that she was still in a coma. In June 2012, Horn told "The Sunday Times" that his wife was not in a coma, but, "She cannot speak, move, or smile. The only expression she can show is of discomfort." Jill Sinclair died of cancer on 22 March 2014, aged 61.