This story has been updated.
Former Vice President Dick Cheney's daughters, Mary and Liz, have taken their disagreement over gay marriage public again, trading barbs online and on television.
Mary, who is a lesbian, took to Facebook over the weekend to say that her sister Liz, who is running for U.S. Senate in Wyoming, is on the "wrong side of history."
The response came after Liz issued her latest comments opposing same-sex marriage during an appearance on "Fox News Sunday." The elder sister told host Chris Wallace that she disagrees with Mary on the issue, The Washington Post reported.
In this Feb. 18, 2010 photo former Vice President Dick Cheney hugs his daughter, Liz Cheney, after she surprised the Conservative Political Action Conference by bringing him as her guest in Washington. (AP/Cliff Owen)
"I love Mary very much. I love her family very much. This is just an issue on which we disagree," Liz Cheney said.
Mary and wife Heather Poe weren't happy after seeing these comments, taking to Facebook to respond formally. Poe posted her views in a message on her Facebook account and Mary subsequently shared the comments on her public page.
"Liz has been a guest in our home, has spent time and shared holidays with our children, and when Mary and I got married in 2012 -- she didn’t hesitate to tell us how happy she was for us," Poe wrote. "To have her now say she doesn’t support our right to marry is offensive to say the least."
Poe also said, "Yes Liz, in 15 states and the District of Columbia you are my sister-in-law."
Image source: Facebook/Heather Poe
Mary Cheney added that she believes her sister is "on the wrong side of history" when it comes to gay rights.
This isn't the first time the two have disagreed publicly. Mary Cheney said her sister was wrong on gay marriage in August as well, the Post reported.
Liz has defended her views in the past and said she believes that rather than a federal ban, states should make their own gay marriage laws.
"I am not pro-gay marriage," she said in a statement from her campaign. "I believe the issue of marriage must be decided by the states and by the people in the states, not by judges and not even by legislators, but by the people themselves."
The New York Times reported Sunday night that Liz Cheney declined to respond specifically to the Facebook messages. She said in an email, "I love my sister and her family and have always tried to be compassionate towards them. I believe that is the Christian way to behave."
Dick Cheney weighed in last month on the disagreement between his daughters in an interview with CNN. Rather than taking a side, he said Liz and Mary are capable of speaking for themselves.
"My position on -- on that issue is well known ... and I've stated it in 2000 in a debate with Joe Lieberman," he said. "It hasn't changed and I'll let my daughters speak for themselves."
In a statement released Monday, Dick Cheney and his wife, Lynne, added, "This is an issue we have dealt with privately for many years, and we are pained to see it become public. Since it has, one thing should be clear. Liz has always believed in the traditional definition of marriage."
The parents went on to say that Liz has always treated Mary with respect, but that her kindness "shouldn't be used to distort her position," Politico reported.
Watch Dick Cheney discuss this around the 5:00 mark:
Liz Cheney is running to unseat fellow Republican Mike Enzi.
(H/T: The Washington Post)