Tight ankles ? Here we do a short little video for mom.

Gain strength in the anterior compartment to achieve posterior compartment length. Stretching calf is not enough when the calf is tight due to increased neurologic protective tone, possibly an attempt to protect the ankle mortise joint.
So, if stretching is not the solution, look to increase facilitation and strength of the weaknesses in the other compartments.  You just might feel the tightness melt away without stretching at all !

Spindle responses and golgi tendon organ responses. The more you know about the nervous system the smarter your treatments will be.

The Gait Guys, using the functioning of the  nervous system to get the responses we want.