Sawyer got a new "walker" this week.... yes, you can still find these online. And, they come with built-in breaking systems so if any of the four wheels are not touching the ground the breaks kick-in and freeze the walker in place.
All that safety talk - he loves it!!! It makes all kinds of noise and gives him his freedom to explore. He is still fairly slow moving and goes for short distances, but I know that won't last for long....