WASHINGTON – Former first ladies Hillary Clinton and Michelle Obama provided a signal boost on Monday to another former first lady, Laura Bush, for her opinion piece slamming the Trump administration’s practice of separating families at the border.

Speaking at a women’s forum award ceremony on Monday, Clinton also said Trump’s claim that the Democrats were to blame for the separations was an “outright lie.”

Bush wrote in The Washington Post on Sunday that the practice was “cruel” and “immoral.” The scathing public admonishment from Bush was rare but drew praise from both her predecessor and successor.

“The test of any nation is how we treat the most vulnerable among us,” Clinton said at an event in New York. “Laura Bush made that case eloquently in The Washington Post this weekend. … She is absolutely right.”

Obama took to Twitter to back Bush, retweeting her link to the piece.

“Sometimes truth transcends party,” the former first lady wrote.

The Trump administration has come under withering criticism from Democrats and Republicans alike for the current zero-tolerance immigration policy being implemented at the border. The policy has led to days of heart-wrenching stories about families being separated, coverage that has blanketed national and local television.

Trump and his aides have responded defensively to the rebukes and the President has tried to falsely blame Democrats for the issue, hoping that scorn will bring them to the table to negotiate a deal. Immigration animated Trump’s 2016 campaign and he has sought to make good on his hardline stance throughout his 17 months in office.

“What is happening to families at the border is horrific,” Clinton said at the award ceremony. “Every human being with a sense of compassion and decency should be outraged.”

The former Democratic presidential nominee, who lost to Trump two years ago, also slammed Attorney General Jeff Sessions for arguing that the Bible justifies this type of treatment on the border.

“Nor are these policies rooted in religion,” Clinton said. “In fact, those who selectively use the Bible to justify this cruelty are ignoring a central tenant of Christianity.”

She added: “I went to a lot of years of Sunday school. I even taught it from time to time. … What is being done using the name of religion is contrary to everything I was ever taught. Jesus said suffer the little children onto me, he did not say let the children suffer.”

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