Former Texas first lady Rita Crocker Clements has died at age 86.

A son-in-law, Jim Moroney, says Clements died Saturday at her Dallas home. Moroney, who's publisher of The Dallas Morning News and CEO of the A.H. Belo Corporation, said Sunday that his mother-in-law died of complications due to Alzheimer's disease.

Clements was a key adviser to her husband, Bill Clements, an oilman and the first Republican governor of Texas since Reconstruction. He served two terms from 1979-January 1983, and 1987-January 1991.

Rita Clements in 1953 earned an undergraduate degree from the University of Texas at Austin. She later became a University of Texas System regent.

The ex-first lady was known for her efforts to preserve the state's heritage and renovation of the Governor's Mansion.

Bill Clements died in 2011.