BILLY CALLENDER said he joined the Knights for a simple reason: to help people. He displayed that desire selflessly years ago when 4-year-old daughter Elizabeth needed a kidney; Billy donated one of his. “You just do it,” he said matter-of-factly. The kidney lasted 16 years, and Beth lived another six years after that, passing away in July 2011. Billy and wife Davida will celebrate their 30th anniversary in February. They have another daughter, Libby, who is married to Chris Cyrek and has two children – Robert (12) and Liliana (almost 3). Billy grew up in Oak Cliff, has been a sales rep for Frito Lay for 17 years and went through RCIA almost 10 years ago. Among the Callenders’ many parish activities is overseeing the monthly Marriage Enrichment get-togethers.