Trump told a kid that the wall's being built. So far, his administration has replaced fencing that was already in place, but work could be progressing on other sections.

"It's a 2,000-mile border, but much of it has mountains and region where you can't get across so we're looking at between 500 and 550," Trump said.

Said the creator of the GoFundMe raising funds for the wall, "I've been receiving thousands of emails from citizens who have waited in line to become Americans and completed this process the legal way."