Every day during his years of service, his girlfriend Sophie sent him a letter.
Sophie became his wife and they spent 55 years together. She died in 2001.
When he was 65, South retired but stayed active woodworking, gardening, golfing and attending church.
He finally moved into Brookdale Senior Living in the Fort Worth suburb of Watauga, Texas, at the age of 98, CNN reported.
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His only child, Jim South, said there are big things planned for his dad's big day including a three-day celebration this year, including a round of golf, dinner of chicken fried steak and catfish and spending time with family.
If you want to help mark the occasion, you can send a card that will be hung on the wall in his room. The address is:
5800 North Park Drive
Watauga, Texas 76148.