Question: Ranked the 129th richest family in the United States, where has their son served as the co-chief executive officer of?
Context: Léo Apotheker (born September 18, 1953, in Aachen) is a German business executive.  He served briefly as the chief executive officer of Hewlett-Packard from November 2010 until his firing in September 2011.  He also served as co-chief executive officer of SAP from April 2008 until he resigned in February 2010 following a decision by that company not to renew his contract. Charles Wickliffe "Wick" Moorman IV (born 1953 in Hattiesburg, Mississippi) is an American businessman and railroader.  Moorman is currently the co-Chief Executive Officer of Amtrak, where he formerly served as President and CEO.  Prior to his hiring by Amtrak, Moorman served as chairman, president and CEO of Norfolk Southern Railway.  At Norfolk Southern, he succeeded David R. Goode on February 1, 2006.  Moorman served as president from 2004 to 2013 and chief executive officer from 2005 until his initial retirement in 2015. Philippe Bourguignon (born 1948) is a French businessman who served as the chief executive officer of Euro Disney, executive vice president of Disney Europe, the chairman and chief executive of Club Med, and the co-chief executive officer of the Davos-based World Economic Forum in 2003 and 2004.  He is vice chairman of Revolution Places, founded by America Online (AOL) cofounder Steve Case and is the executive co-chairman of Exclusive Resorts. The Lindner family is a family that has been prominent in the Cincinnati metropolitan area since the mid-20th century.  They are known for their work in the insurance and investments business.  As of 2015, "Forbes" ranks them as the 129th richest family in the United States.  They are also known for their involvement in professional sports; Carl Jr. was a part owner and CEO of the Cincinnati Reds, Carl III is the majority owner and CEO of FC Cincinnati, and the family's contributions to the Western & Southern Open led to its venue being titled the Lindner Family Tennis Center. Steven "Steve" D. Black is the former Vice-Chairman of JP Morgan Chase & Co..  He previously served as the Co-Chief Executive Officer of JP Morgan, the investment banking subsidiary of JP Morgan Chase.  He is a 1974 graduate of Duke University, and has served on the New York Development Council.  In October 2009 he was succeeded by Jes Staley. Carl Henry Lindner III is an American businessman.  He has served as the co-chief executive officer of American Financial Group since January 2005.  He has also acted as chief executive officer and majority owner of FC Cincinnati since the club's founding in 2015.  He is the son of Carl Lindner Jr. and a prominent member of the Lindner family. Siddharth N. "Bobby" Mehta was former CEO and vice chairman of HSBC North America.  Mehta served as an Advisor of TransUnion since December 31, 2012.  Mehta serves as consultant of TransUnion.  He served the chief executive officer and president of TransUnion from August 2007 to December 31, 2012, and Transunion Financing Corp. until December 31, 2012.  From May 2007 to July 2007, he served as a consultant to the board of directors at TransUnion.  He served as the chief executive officer and president of TransUnion until December 31, 2012.  He served as the chief executive officer of TransUnion LLC.  He served as chairman of the board and chief executive officer of HSBC Finance Corporation from April 2005 to February 2007.  He served as chief executive officer and president of TransUnion LLC from 2007 to 2012.  From 1998 to 2007, he held a variety of positions with HSBC Finance Corporation and HSBC North America Holdings, Inc.  Mehta served as chief executive officer of HSBC North America until February 2007.  Mehta served as consultant of TransUnion since May 2007 until July 2007.  Mehta served as group managing director of HSBC Holdings PLC of HSBC Finance Corp. since April 30, 2005, and its unit chief executive officer since March 2005.  He served as the chief executive of HS BC North America Holdings Inc., of HSBC Finance Corp., from March 2005 to February 15, 2007.  He served as an executive chairman of HSBC Financial Corporation Limited since April 2005 and served as its chief executive officer from April 2005 to February 15, 2007.  He served as the chief executive officer of HSBC Bank USA, N.A. until February 2007.  He served as the chief executive officer of HSBC North America Holdings Inc. since March 2005.  He served as chairman and chief executive officer of HSBC Financial Corp., Ltd.  He oversaw HSBC's global credit card services, its North American consumer lending and mortgage services businesses and its first mortgage operation.  He was also responsible for corporate marketing, strategic planning and corporate development for HSBC North America Holdings Inc. and had responsibility for the strategic management of credit cards throughout the HSBC Group.  Mehta served as group executive of Credit Card Services, Auto Finance and Canada of Household International Inc., since July 2002.  He worked at MasterCard’s U.S. region board since March 2000.  Mehta joined Household International Inc., in 1998.  He served as senior vice president of The Boston Consulting Group in Los Angeles and co-leader of Boston Consulting Group Financial Services Practice in the United States.  Mehta served as a director of Global Board of MasterCard Incorporated since March 17, 2005.  He served as unit chairman of HSBC Holdings PLC and served as its board member since March 2005.  He served as vice chairman and director of HSBC Financial Corporation Limited., (Formerly Household International Inc.).  He has been a director of Avant Credit Corporation since December 18, 2014.  He has been an independent director of The Allstate Corporation since February 19, 2014.  He serves as a member of the advisory board at Core2 Group, Inc.  He has been non-executive independent director at Piramal Enterprises Ltd since April 1, 2013.  He serves on the boards of Datacard, Chicago Public Education Fund, University of Chicago Laboratory Schools, The Economic Club of Chicago, The Field Museum and Myelin Repair Foundation.  He serves as a director of TransUnion Corp. and TransUnion LLC.  He served as a director of MasterCard International Inc. (also known as MasterCard Worldwide) (formerly, MasterCard Inc.), since March 17, 2005.  He served as a director of HSBC Financial Corp.  Ltd.  He has been a director of TransUnion since April 2012.  Mehta serves on the board of international advisors for the Monterey, California, Institute of International Studies and is a member of the Financial Services Roundtable.  He also serves on the board of advisors for the Myelin Repair Foundation.  Mehta holds a Bachelor of Arts in economics from the London School of Economics and Masters of Business Administration from the University of Chicago.  He stepped down as head of the North American unit after the lender raised its forecast for bad loans in the U.S.  He is of Indian descent. Eric Francis Billings (born 1954) is Chairman and Chief Executive Officer of FBR Capital Markets Corporation (NYSE: FBR).  He has held this position since the company's formation in June 2006.  He has also served as a director of the Company since June 2006.  Billings is also the Chairman and Chief Executive Officer of FBR Group, a position he assumed in April 2005.  Prior to April 2005, Billings served as Co-Chairman and Co-Chief Executive Officer of FBR Group. Terry Semel (born February 24, 1943) is an American corporate executive who was the chairman and CEO of Yahoo! Incorporated from 2001 to 2007.  Previously, he spent 24 years at Warner Bros., where he served as chairman and co-chief executive officer.  He resigned as CEO due in part to pressure from shareholders' dissatisfaction over his compensation (in 2006, salary $1, stock options worth $70 million) and performance.  He is also the founder of Windsor Media which has produced "Rules Don't Apply" starring Lily Collins and Warren Beatty. Daniel A. (Dan) Ninivaggi (born June 27, 1964) is an American lawyer and business executive.  Ninivaggi served in various executive positions with Lear Corporation, a U.S.-based Tier 1 automotive supplier.  He then served as President and CEO of Icahn Enterprises L.P., the principal investment vehicle of U.S. billionaire Carl C. Icahn, from 2010 to 2014.  From February 2014 to March 2017, Ninivaggi was Co-Chief Executive Officer and Co-Chairman of the Board of Directors of Federal-Mogul Holdings Corporation, based in Southfield, Michigan, USA.  On March 8th, 2017 Ninivaggi assumed the role of managing partner of the automotive segment of Icahn Enterprises L.P., which owns Federal-Mogul.  He presently serves as CEO of Icahn Automotive Group LLC, owner of automotive distribution and service businesses, including Pep Boys.   Ninivaggi has served on the Board of Directors of Hertz Global Holdings, Inc. since 2014.  
Answer: American Financial Group since