Is it? He took a plane, surely

Bushby's walk has been extensively covered in the press (and in his own book about the Americas leg). Mexico served as his base while waiting for visas, permissions, and sponsorship, so he was flying back there and then, once he could continue, he flew back to the exact coordinates he had left off and started walking again from there.

There has been plenty of press coverage of how Bushby was unable to see the child, because the mother took the child to Northern Ireland where Bushby was unable to follow due to his military status.