Si, born (1948-04-27) April 27, 1948 (age 73), is Phil's brother, a Vietnam War veteran, and uncle to Phil and Miss Kay's four sons. Si worked at Duck Commander making the reeds that go into every duck call. Si is known for his storytelling, and his constant use of the expressions "Hey!" and "Jack" (which ends many of his sentences), and for his ever-present emerald green Tupperware cup, (which his mother sent him while he was stationed in Vietnam); ever-filled with iced tea. Si retired from the Army in 1993 with the rank of Sergeant First Class (E-7). Robertson is recognized for his military career with an exhibit at the Chennault Aviation and Military Museum in Monroe, Louisiana. Si has been married to Christine for 48 years — she, with the exception of the series finale, has declined to appear on the show. He and his wife Christine have two children, Trasa and Scott. Scott has not appeared on the show, although Trasa made a brief appearance in the episode "Stand by Mia".