Ker was born in Philadelphia, Pennsylvania, and was the only son of George and Anne Ker.[1] His father George immigrated to the United States from Scotland, and had previously served in the British Army as a Buckingham Palace guard.[1] When Ker was young, his family moved to Florida, and his father worked several jobs to support the family in Dunedin, Florida; running a lawn service during the day and working at a convenience store at night. After school, and during weekends and summers, Ker followed his father's steps with his work ethic.[1]
In the mid-1970s, George managed the kitchen at a sports restaurant in Clearwater, Florida, where Ker worked as a busboy while he was in high school.[1] During school semester breaks and vacations, he also waited tables and cooked in the kitchen.[1]
Ker attended Dunedin High School in Dunedin.[2] During his junior year in high school, he decided to become a professional football player.[1] He had not played high school football before his junior year, but he started working out; after beginning high school at 145 pounds, he bulked up to 210.[1]
As a senior, he was named All-Conference and the Dunedin Falcons football team won a Pinellas County championship, but no Division I football programs recruited him to play college football. He graduated in 1980, but he wanted to play at a big school to improve his chances of being drafted in the NFL, so he worked out during the first year after graduation, adding another fifty pounds to his six-foot, four-inch frame.[1]
The Florida Gators football coaches were convinced of Ker's talent and offered him a football scholarship to attend the University of Florida for his last 2 years of eligibility in 1983 and 1984.[3] Ker's nickname among his Gators teammates was "Big Daddy," and he could bench-press up to 515 pounds making him one of the strongest players in college football.[1]
He played two years for coach Charley Pell and coach Galen Hall's Florida Gators football teams. As a senior, he was a starter at right tackle on the Gator's 1984 squad that, at the time, was considered the finest Gators football team ever. The Gators' outstanding offensive line was called "The Great Wall of Florida," and included Ker, Phil Bromley, Lomas Brown, Billy Hinson and Jeff Zimmerman.[4]
Behind the blocking of Ker and his Great Wall teammates, the Gators' quarterback Kerwin Bell, fullbackJohn L. Williams and halfbackNeal Anderson led the Gators to a 9–1–1 overall win–loss record and won their first Southeastern Conference (SEC) championship with a conference record of 5–0–1.[5] He was recognized as a second-team All-SEC selection and an honorable mention All-American following the 1984 season.[3]
He was moved to guard, but only played five games as a 23-year-old rookie, after being placed on the injured reserve list with a back injury on October 23.
Ker became the Cowboys' highest-paid offensive lineman,[1] and started in eighty-six of the Cowboys' ninety-one regular season games from 1986 to 1990.
Carlson, Norm, University of Florida Football Vault: The History of the Florida Gators, Whitman Publishing, LLC, Atlanta, Georgia (2007). ISBN0-7948-2298-3.
Golenbock, Peter, Go Gators! An Oral History of Florida's Pursuit of Gridiron Glory, Legends Publishing, LLC, St. Petersburg, Florida (2002). ISBN0-9650782-1-3.
Hairston, Jack, Tales from the Gator Swamp: A Collection of the Greatest Gator Stories Ever Told, Sports Publishing, LLC, Champaign, Illinois (2002). ISBN1-58261-514-4.
^The title was later vacated by the SEC university presidents because of NCAA rules violations committed by Charley Pell and the Gators coaching staff between 1979 and 1983, before Ker's arrival in Gainesville.