One day after Khloe Kardashian Odom went on a Twitter rant to slam the two women claiming Robert Kardashian is not her biological dad, her mother, Kris Jenner, has spoken out, calling the paternity rumors "crap."

"I have never heard such crap in my life," Jenner said today on " Good Morning America."  "Get a life."

Jenner's comments were targeted at the two women who married her late husband, Robert Kardashian, after their 1990 divorce.

Both women broke their silence to Star magazine Wednesday in an article that reopens rumors and claims that Odom, the youngest of the three Kardashian sisters, is not a Kardashian.

"Khloe is not his kid. He told me that after we got married," ex-wife Jan Ashley, 63, the first spouse after Jenner, told Star.  "He just kind of looked at me and said (it) like it was a matter of fact.

"Robert did question the fact that Khloe was his," Kardashian's third wife, Ellen, 63, also told the mag.

Comments like those from her former stepmoms prompted an immediate and angry reply from Odom on Twitter.

"The audacity you have to mention my father's name like this! Should be ashamed of urself! I let a lot of things slide but this one is really low," the 27-year-old wife of basketball star Lamar Odom wrote on Wednesday.

"YOU ARE DISGUSTING! (yes you know who YOU are)," she wrote.

Jenner, 56, the one woman in the world who knows the truth, similarly targeted her ire at the two women making the claims, without explicitly saying that Robert Kardashian is, indeed, Khloe's dad.

"I mean I was there. I gave birth.  I know who the dad was," she said on "GMA," while also calling the claims "silly."

"Maybe it makes somebody relevant for the day," she said of why her ex-husband's wives spoke out.

Odom has had to publicly dodge paternity rumors like those brought up in the Star article ever since she herself questioned whether she might be adopted in a 2009 episode of  the family's reality TV show, " Keeping Up With The Kardashians," on E!.

In the episode, Odom, encouraged by her sisters Kourtney and Kim, swabs her mom's mouth for a DNA test.

"We did a whole episode on stuff like this because it's the family joke because Khloe was blonde and not dark-haired," Jenner explained in her appearance on "GMA" from Las Vegas, where she will judge the "Miss America" pageant this Saturday.

"It's what you sign up for, I guess, when you put yourself out there," she said of the family's seeming inability to stay out of tabloid headlines.  "We're an open book."

Jenner found herself in the headlines when she admitted in her recently published autobiography that she cheated on Kardashian during the marriage, but said the "insanely intense affair" with an unnamed younger man came after the birth of Odom and her siblings.

Today, she is married to former Olympian Bruce Jenner, whose name also appeared in the article in Star, accused by Ellen Kardashian of being a cross dresser with a secret collection of wigs, dresses, high heels and lacy lingerie.

"That is such a '70s story," Jenner said today of those rumors.  "It's like now they're running out of things to talk about. "

"It's just so crazy," she said.