Question: Who is the murdered son of presenter of the weeknight edition of "Nine News Adelaide"?
Context: Kym Dillon (born 19 June 1960) is the former weekend sports presenter for Nine News Adelaide.  He is also part of the successful sports coverage and football commentary team at FIVEaa.  Prior to his media career he played football for SANFL clubs North Adelaide and West Torrens in the late 1970s and early 1980s, winning a Reserves Magarey Medal in 1982. Amber Simone Sherlock (born 1 December 1975, née Higlett) is an Australian journalist, television news presenter and reporter.  She currently presents the weather on "Nine News Sydney" and hosts a daily national one hour news bulletin "Nine News Now". Will McDonald (born 1979) is a South Australian journalist, currently presenting the weekend news for Nine News Adelaide. Georgina McGuinness (née Allan, formerly Thomas) was the anchor of "Nine News Adelaide"'s weekend 6pm news bulletin from 1989 to 2011. Bevan Spencer von Einem (born 1945), also known as Bevan von Einem, is a convicted child murderer from Adelaide, South Australia and suspected serial killer.  An accountant by profession, he was convicted in 1984 for the murder of 15-year-old Adelaide teenager Richard Kelvin, the son of local television and radio personality Rob Kelvin.  Einem is currently serving life imprisonment in Port Augusta Prison. Rob Kelvin (born 20 September 1944) is a former television news presenter who lived in Adelaide, South Australia.  He was a presenter of the weeknight edition of "Nine News Adelaide" produced by NWS-9.  Kelvin presented the bulletin with Kevin Crease until February 2007, when Crease retired after being diagnosed with cancer.  Kelvin presented with Kelly Nestor and then Michael Smyth until he retired in December 2010. Nine News Queensland is the weeknight, flagship news bulletin of the Nine Network.  It is screened in Brisbane, and across south-east Queensland, on weeknights, while on weekends it is screened state-wide as well as in the Northern Territory.  Like all "Nine News" bulletins, the Queensland bulletin runs for one hour, from 6PM every day.  It comprises local, national and international news, as well as sport, weather and finance. Warren Gary Tredrea (born 24 December 1978) is a former Australian Rules Footballer with the Port Adelaide Football Club in the Australian Football League (AFL) and current Weekday Sports Presenter on "Nine News Adelaide".  Since his retirement from football, he has become a sports media personality featuring on "Nine News Adelaide", Triple M and in The Advertiser newspaper. Emmy Kubainski (born 1986) is an Australian journalist and news presenter.  Kubainski currently presents Nine Live Perth at 4pm and is "Nine News Perth"'s co-anchor with Tim McMillan presenting the weeknight 6.00pm bulletin. Andrew Lofthouse (born 1962 or 1963) is a television and radio newsreader based in Brisbane, Australia.  The English-born former teacher is the weeknight presenter of "Nine News Queensland" with Melissa Downes, having previously presented on weekends.  Prior to working at "Nine News", he presented the weekday evening news bulletin of "ABC News Queensland", as well as reading the news on the 612 ABC Brisbane radio station on weekday afternoons.
Answer: Richard Kelvin