Not really the most sensible thing I have ever heard.
As others have said buying an unbroken pony for 2 novice children is crazy.
This sadly is the reason there are so many bad horses out there,nearly all man made.
Please consider sending your horse to a professional yard to be broken andin th emean time send the kids to a riding school to learn on safe ponies.They will then need continuous lessons with the pony so that she does not learn bad habits.

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