Question: Who is a cast member of the show on which David Brandner is a character?

full_context: Document 1: Arno Brandner: Arno Brandner is a fictional character on German soap opera "Verbotene Liebe (Forbidden Love)". The character was portrayed by actor Konrad Krauss, who first appeared in the series premiere on 2 January 1995.
Document 2: Jana von Lahnstein: Jana von Lahnstein ("née" Brandner) is a fictional character in the German soap opera "Verbotene Liebe" ("Forbidden Love"). The character was played by the actress Friederike Sipp from 1 October 2002 to 21 March 2005. The character was recast with Vanessa Jung, who played the role from 23 March 2005 to 20 February 2008.
Document 3: Paul Brandner: Paul Brandner is a fictional character of German soap opera "Verbotene Liebe (Forbidden Love)". The character was portrayed by actor Tobias Schönenberg from April 15, 2005 to April 27, 2007. Paul was written out, when Schönenberg decided not to re-sign with the show .
Document 4: Florian Brandner: Florian Brandner is a fictional character on German soap opera "Verbotene Liebe (Forbidden Love)". The character was first played by Frédéric A. Komp from 2 January 1995 to the fall of 1996 and again in February 1997 and from June to October 1998. The character was recast with actor Alex Huber four years later, on 12 July 2002. Huber left after one and a half year, when the character was written out. He made his last appearance on 15 January 2004.
Document 5: Lydia Brandner: Lydia Brandner (divorced von Lahnstein) is a fictional character from the German soap opera "Verbotene Liebe" (Forbidden Love). The role was originated by actress Theresa Underberg on 16 January 2008. Theresa announced on 21 December 2010 that she will leave the show in early 2011. She made her last appearance on 29 March 2011.
Document 6: Judith Hagendorf: Judith Hagendorf is a fictional character on the German soap opera "Verbotene Liebe (Forbidden Love)" portrayed by actress Katrin Heß from February 18, 2008 to September 15, 2009, when the character was surprisingly written out without any conformation from the production.
Document 7: Timo Mendes: Timo Mendes is a fictional character from the German soap opera "Verbotene Liebe (Forbidden Love)". Remo Schulze debuted in the role on 23 June 2011. Timo is the son of Julia von Anstetten and her first husband Tim Sander.
Document 8: Clarissa von Anstetten: Clarissa von Anstetten (née Prozeski and formerly Kaufmann) is a fictional character on German soap opera "Verbotene Liebe (Forbidden Love)". The character is played by actress Isa Jank from the show's debut on 2 January 1995 to 5 September 2001 and again since 21 June 2011. She left the show again on 20 March 2013.
Document 9: Jan Brandner: Jan Brandner is a fictional character on German soap opera "Verbotene Liebe (Forbidden Love)". The character was played from the show's debut on January 2, 1995 to August 27, 1997 by actor Andreas Brucker. In March 2011, the role was surprisingly recast with actor Hubertus Grimm; reinstating the Brandner family and the original story of the show. Grimm debuted in the role on June 23, 2011. The role was reactivated on short-term for a special of the show on the Spanish island Mallorca. The character made his last appearance on January 18, 2012.
Document 10: Fabian Brandner: Fabian Brandner is a fictional character on the German soap opera "Verbotene Liebe (Forbidden Love)". The character was portrayed by Shai Hoffmann from January 22, 2008 to August 14, 2008 and in guest appearances from January 12, 2009 to January 22, 2009.
Document 11: Julia Mendes: Julia Mendes (born Prozeski, adopted von Anstetten and formerly Sander) is a fictional character from the German soap opera "Verbotene Liebe (Forbidden Love)", played by Valerie Niehaus. She is introduced in the series' premiere on January 2, 1995. She departed from the series in July 1997, when Niehaus decided to pursue other roles. The role was surprisingly recast with well-known actress Nina Bott in 2011; reinstating the Brandner family and the original story of the show. Bott appeared for the first time on-screen on June 23, 2011. She eventually finished shooting her story arc in October 2011 and last appeared on January 18, 2012. The character is known as the first protagonist of the show and her main story focuses around the incestuous love to her twin-brother Jan Brandner.
Document 12: David Brandner: David Brandner is a fictional character on the German soap opera "Verbotene Liebe (Forbidden Love)" portrayed by actor Sven Koller from September 11, 2008 to June 15, 2010.
Document 13: Matthias Brandner: Matthias Brandner is a fictional character from the German soap opera "Verbotene Liebe (Forbidden Love)" portrayed by actor and entertainer Thomas Ohrner. He made his first appearance on screen on 15 January 2008 and had his final appearance on 14 December 2010.
Document 14: Nathalie Brandner: Nathalie Brandner (née Käppler, formerly von Lahnstein) is a fictional character from the German soap opera "Verbotene Liebe (Forbidden Love)". The character is portrayed by actress Jenny Winkler. She first appeared on 12 November 2004 and had her final appearance on 14 December 2010.
Document 15: Tanja von Lahnstein: Tanja von Lahnstein (née Wittkamp, formerly von Anstetten, Rai and von Lahnstein) is a fictional character from the German soap opera "Verbotene Liebe (Forbidden Love)", played by actress Miriam Lahnstein. She made her first appearance on-screen on 21 June 1995 and left after three years in May 1998. Lahnstein returned to the role in 2001, where she was seen from 24 April to 5 October. She came back another three years later and reappeared on 16 April 2004. Lahnstein left the show for a short time, while being on contract, from June 2005 to March 2006 and from March to December 2007 during the pregnancy of her two children. She left again in December 2009 and returned in April 2010.
ground_truth: Valerie Niehaus
sub_queries: What show is David Brandner from? Answer: Verbotene Liebe
Verbotene Liebe >> cast member Answer: Valerie Niehaus