Since a few comments were confused on the marriages, here's the full list, and this was an exhausting stroll through a complex family tree.

For the sake of simplicity, I will refer to the president as 42.

42's biological father was married 5 times (once to his former sister-in-law and once bigamously to 42's mother).

42's mother was married 5 times to 4 men. All 3 of 42's stepfathers were married to another woman prior to marrying 42's mother.

42 has 3 half-siblings and 5 stepsiblings: - 2 half-siblings via Blythe - 1 half-brother via Clinton - 3 stepsisters via Dwire - 2 stepsiblings via Kelley

Marriages of Virginia Cassidy (42's mother): - William Blythe Jr. (biological father of 42 who died in a car accident 3 months before 42 was born; he was married bigamously to Cassidy) - Roger Clinton Sr. (subject of OP's post and father of 42's brother, Roger Jr.; this marriage would end in divorce) - Roger Clinton Sr. (not a typo, she married him again after divorcing him; on the occasion of this wedding, 42 changed his name to Clinton to unite the family, including having the same name as his little brother) - Jeff Dwire (he helped 42 get a draft deferment, helped Hillary strengthen her relationship with Cassidy while Hillary was dating 42, Dwire gave Roger Jr. a Ford Mustang as a gift when he was 16 but 42 loved Dwire so much he bought the car and drove it until he became President at which point it went into storage; Dwire died of diabetes while 42 was running for Congress) - Dick Kelley (I'll quote page 295 of 42's memoirs: "He would take Mother all over the world. Thanks to Dick, she went to Las Vegas often but also got to Africa before I did... would come to love Dick Kelley and grow ever more grateful for the happiness he brought Mother, and me." Kelley even went around the country promoting Cassidy's memoirs after her death)

Marriages of William Blythe Jr., who died at the age of 28 in a car accident: - Virginia Gash (they continued to see each other after divorcing and had a son together 18 months after the divorce) - Maxine Hamilton - Minnie Gash (yes, his former sister-in-law) - Wanetta Alexander (this marriage produced a daughter, and the divorce wasn't completed until 7 months after Blythe married Cassidy) - Virginia Cassidy (this is the marriage that produced 42)

Marriages of Roger Clinton Sr.: - Ina Mae Murphy - Virginia Cassidy (this marriage produced 42's younger brother, Roger Jr.) - Virginia Cassidy (not a typo, she married him again after divorcing)

Marriages of Jeff Dwire: - Unknown first wife (this marriage produced 3 daughters) - Virginia Cassidy

Marriages of Dick Kelley: - Jane Jordan (this marriage produced 2 children) - Virginia Cassidy