Senior White House adviser Kellyane Conway said Wednesday president Trump “discovered” there was no need for his wall to cover the entire U.S.-Mexico border to work, which experts have been saying since 2016 and Trump himself even referenced back in July.But Conway made it sound like a revelation. She explained some of the president’s reasoning in an interview with CNN: "There are rivers involved, I'm told.”The president’s sources — a map, presumably — are correct, as the 1,900-mile Rio Grande runs the entire border between Texas and Mexico.Trump said Wednesday any deal on reinstating the DACA program, which protects immigrants who came here as children, would have to include the wall along the Southern border with Mexico, a fervent campaign promise. He said as recently as Saturday he still thinks Mexico will pay for it (they’ve repeatedly said they won’t), but he just asked for $18 billion from Congress for it anyway.Cover: A family has a picnic on the bank of the Rio Grande river in Miguel Aleman, Tamaulipas state, Mexico, located across from Roma, Texas.