Donna Adelson, the matriarch of a wealthy South Florida family who was convicted in the hired killing of her former son-in-law, was sentenced Monday to life in prison for her role in the 2014 murder-for-hire of Daniel Markel. A prominent Florida State University law professor, Markel was locked in a bitter custody battle with his ex-wife, Adelson's daughter, when he was gunned down in 2014 at his home in Tallahassee.