According to Atlanta Journal-Constitution, Diane preceded her father's death, which was 12/26/2010.

 Henry TEAL 
Date: December 28, 2010   Publication: Atlanta Journal-Constitution
TEAL, Henry Mr. Henry Teal of Newnan passed away Sunday, December 26, 2010. He was preceded in death by his wife, Faith Marie Teal; daughter, Diane Marie Agan, and is survived by his son, Jeff Teal and his wife Tina of Newnan; Chris Teal and his wife Jennifer of Sharpsburg; grandchildren, Jamie, Jessica, Justin and Kristi Teal.