You should put her into hot water and wait till her body becomes soft, then try and move her legs into a proper position, try and put something in-between the legs so they stay in place. After you're happy with the position of the legs move the pony to the freezer (you can let her cool off normally-outside freezer, but from what I know the freezer just helps a bit more).
After she's cool just let her dry off for a bit and she'll be fine.
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