their colleagues in the west wing who are used to fighting. they say this was different. we're told john kelly got the angriest when john bolton made a remark about the dhs secretary saying she needed to do her job over at dhs while they were talking about these border crossings, and that set john kelly off. kirsten nelson, he brought her to the west wing with him. and he was the won who convinced president trump to put her in to lead dhs. but the question is, this has sparked resignation fears. people think that john kelly could resign over this argument, and that it was so bad, one person equated it to a falling out, and said they were worried he could resign any minute now. >> do we know what the disagreement revolved around? was it just around secretary neilson, whether she was doing a good job or not? >> reporter: the president denied knowing about the screaming match, but sources