Here is one of the few pictures that actually shows Alex riding a bike, right there, right in the middle of the frame, suspended in motion. He just learned how to ride without the training wheels last week. Thanks to Raul or rather his brother's way of training: starts with "duck walking" seated on the bike, don't start pedal until building up some balance and momentum. That is don't combine moving forward with pedaling in the beginning. The method works well in Alex's case.