"The separation of illegal alien families is the product of the same legal loopholes that Democrats refuse to close and these laws are the same that have been on the book for over a decade and the president is simply enforcing them", Sanders said.
"I don't care if you have opinions like that", Watters said.
"That's not what I said", she replied.
But one reporter became emotional when asking Ms Sanders, as a parent, if she had any empathy for the children.
Sanders plans to leave at the end of the year, according to CBS.
Décès d'un septuagénaire après avoir mangé une plante toxique — Pyrénées-Orientales
Sa femme, âgée de 75 ans, a été prise de vomissements et de nausées et a été transportée en urgence à l'hopital. De retour à la maison, la victime et sa femme préparent leur repas avec ces plantes.
She went to the next reporter but eventually CNN political analyst Brian Karem had enough.
In recent months, Border Patrol agents have split up at least hundreds of migrant families under the Trump administration's new "zero-tolerance" policy mandating that every person caught illegally crossing the border face criminal prosecution.
Former communications director Hope Hicks, Jared Kushner's top communications aide Josh Raffel, Trump personal aide John McEntee, congressional communications director Kaelan Dorr, assistant press secretary Natalie Strom deputy media affairs director Tyler Ross and others have moved on.
Sanders has served as Trump's press secretary since July 2017.
On another note, Sarah Sanders is considering leaving her job at the White House.
"If you're going to risk everything, you know - a proper answer for her would have been, 'You know what, we're providing them a Walmart better than what they have in their home country.' That would have been callous but true", he said.
"It's not a policy change to enforce the law", Sanders said as the reporter explained the exact Trump administration policy that prompted the change. And it is going to be harder to find good people to replace them. Staffers who have left or been forced out of their jobs have described a dysfunctional and toxic working environment.