The Border Patrol says arrests in South Texas have fallen to about 100 per day, down from 300 or more in June. The decline could be the result of summer temperatures or a messaging campaign in both the U.S. and the migrants' home countries. No one knows for sure.
Authorities are careful not to say that the crisis has passed. When temperatures subside, children could be back in greater numbers.
The White House has shied away from taking credit for the decrease, which gives the administration more time to deal with immigrants who have already arrived.