Clay Matthews and Hines Ward – 2011 CMT Music Awards – Press Room – Bridgestone Arena – Nashville, TN, USA – Photo Credit: Andrew Evans / PR Photos
Birth Name: William Clay Matthews III
Place of Birth: Northridge, Los Angeles, California
Date of Birth: May 14, 1986
Ethnicity: English, German, possibly Czech and other
Family Background: Clay Matthews is an American football outside linebacker for the Green Bay Packers of the National Football League.
Clay Matthews is the son of Leslie and William Clay Matthews Jr. Leslie Matthews maiden name may have been Zdenek.
Matthew’s paternal grandparents are/were William Clay Matthews Sr. (the son of Howard Lynn Matthews and Elsa Bargmann) and Carolyn K. Matthews.
Source: http://hosting-16052.tributes.com/obituary/show/William-Clay-Matthews-104607442 (obituary of Matthew’s paternal grandfather)