I have a 5 month old filly who is 13.2hh, barely a hand shy of her dam who is about 14.1hh. Her sire is only 15hh, but her grandsire was 16.2hh and the only height in her bloodlines. She is a Tennessee Walker, as are all in her lines. Is this tall for her age? My farrier acted like she was a giant for her age, and he raises tallish QHs.