Daughter, Kristi, is married to Pat Bates, a former PGA TOUR and Web.com Tour member. Bates was a three-time winner on the Web.com Tour in 2001, including the season-ending Web.com Tour Championship. He is now the golf coach at the University of Central Oklahoma.
Biggest thrills in golf were winning the 1980 MCI Heritage Classic, his first TOUR victory, and his first Champions Tour win at the 2000 PGA Seniors' Championship, each by seven strokes.
Lists his father and Labron Harris, Sr. as the most influential people in his golf career.
Got started in the game by working as a caddie for his father in Stillwater, OK.
Has worked with such instructors as Gary Smith, Jim Flick, Stan Utley and Labron Harris.
Attended Oklahoma State his freshman year on a basketball scholarship from the legendary coach Henry Iba.
Was named to the Oklahoma Hall of Fame in August 2007.
Favorite golf course is Oak Tree GC in Edmond, Okla.
Biggest thrill outside of golf was attending Race Driving School with Rick Mears, Bobby Rahal and Al Unser, Sr.
Always keeps a penny in his pocket for good luck.
Nickname is "Tewell Time.".
Other favorites include the Bible, The History Channel, actress Charlize Theron, singer Vince Gill, ice cream and Arnold Palmer.
One course he would like to play is Pine Valley.
Board member of The First Tee of Oklahoma City.
Some of his best friends on the Champions Tour are Bob Gilder, Bruce Lietzke and Gil Morgan.