Because of this claim in a comment:

Does Elizabeth Warren actually have any Native American ancestry?

If she claimed in public she did, but in reality didn’t, then she lied, didn’t she?

Here is Vox explaining the non-issue:

Trump’s comment may be racist against Native Americans, but he’s using it here to sarcastically suggest that Warren really isn’t Native American. (Which, oddly enough, proves that Trump can also be racist while trying to insult someone for being white.)

Trump is referring to a controversy Warren faced over her ancestry during her 2012 Senate campaign.

Warren says she grew up being told that she had Cherokee heritage. “Everyone on our mother’s side — aunts, uncles, and grandparents — talked openly about their Native American ancestry,” she wrote in her 2014 book, A Fighting Chance. “My brothers and I grew up on stories about our grandfather building one-room schoolhouses and about our grandparents’ courtship and their early lives together in Indian Territory.”

Saying you grow up being told X isn’t the same thing as claiming that X is true. I think we all grew up being told a lot of things that weren’t true. I was told that Santa Claus was real.

This became an issue during her campaign when reports emerged that Harvard had once touted her Native American heritage as proof of its faculty’s diversity. Warren, however, couldn’t produce definitive proof of her Cherokee ancestry, and neither could genealogists.

Big woop. She said she was told it. People get things wrong.

This led to speculation that Warren had been a fake “diversity hire,” or that she had abused the affirmative-action system to gain an advantage over other candidates.

However, as Garance Franke-Ruta reported for the Atlantic in 2012, there’s no evidence that Warren ever used claims of Native American ancestry to help her get a job.

And there is, by contrast, evidence that she did not use claims of Native American ancestry to help her get a job.

While Warren was listed as a minority in the Association of American Law Schools Directory of Faculty, she had declined to apply as a minority to Rutgers Law School, and had listed herself as “white” while teaching at the University of Texas. The head of the committee that recruited Warren to Harvard also said he had no memory of her Native American heritage ever coming up, and the 1995 Harvard Crimson article reporting on her tenure made no mention of it.

It’s true, Franke-Ruta learned, that Warren wouldn’t meet the criteria to officially qualify as Cherokee. She only claimed to be 1/32 Cherokee, which is too little to qualify for citizenship in two of the three major Cherokee tribes. She also doesn’t have a known direct ancestor listed on the Dawes Rolls, which is a strict requirement for membership in the Cherokee Nation, or on the Baker Rolls, a requirement of the Eastern Band of Cherokee Indians.

But just because Warren can’t find hard evidence of Native American heritage doesn’t mean she doesn’t have any, Franke-Ruta said — and even if she doesn’t, that wouldn’t make her a liar. Hazy oral histories about Native heritage are especially common in Oklahoma, where Warren grew up, and she would have no particular reason to disbelieve the stories she was told growing up.

Franke-Ruta notes that the shaky reliability of oral history has confounded other public figures — like Madeleine Albright, who didn’t know until reporters discovered it that her own parents had escaped the Holocaust, or Marco Rubio, who mistakenly believed that he was the “son of exiles” from Castro’s Cuba when his parents actually came over before Castro took power.

We don’t always know much about our ancestors, in some cases even our grandparents.

So no – Warren’s saying she was told she had a tiny amount of Cherokee ancestry wasn’t necessarily a lie even if she didn’t in fact have any such ancestry.