When the biggest names in bluegrass needed a fiddler player or bassist, they often called on Billy Joe Foster. His name isn't as well-known as Bill Monroe or Ricky Skaggs, but he played a vital role in their careers. Foster died in late January at age 51 after battling multiple sclerosis. During his career he played in all 50 states and in 15 countries, including shows for princes, kings, and presidents. The Duncan, Okla. native was active up until the end, having played as recently as October 2012 at the Chisholm Trail Opry.