At around the age of two, children walk
with a flat-footed stomp. Their hip joints
will have rotated, so their feet and knees
will now point forward. And they won't
need to use their arms to balance anymore.

At four years old they may still seem a little
flat-footed, but they will be developing
a heel-to-toe walking style. Their knees
and ankles will flex naturally, making their
movement smoother than before, though
they'll find changing speed or direction
difficult. They'll also be getting to grips
with running and jumping.

Throughout this period, they need shoes
which are flexible enough to let their
movement develop naturally, but sturdy
enough to protect them as they become
more active.