Certainly he was not fettered and cramped and prevented from taking exercise like his little sisters.

The princesses of Spain were dressed in wide skirts, spread out over hoops and hiding their feet, from the time they could walk.

The tops of the dresses were as stiff as corselets, and one wonders how the little girls were able to move at all.

As they grew older the hoops became wider and wider, until in one picture of a grown-up princess, the skirts are broader than the whole height of her body.

Stringent Court etiquette forbade a princess to let her feet be seen, but so odd may such conventions be, that it was nevertheless thought correct for the Queen to ride on horseback astride.
It is from the canvases of Velasquez that we know the Spanish Royal Family and the aspect of the Court of Philip IV.