I've seen little charts that tell you the size a foal will mature based on how big they are at what point in their life. I've seen people measuring cannon bone length, I've seen it based on the size of the parents, and I've seen just guesses. In the big horse world they use the string test. But in the big horse world none of these things are more accurate than the guesses. I'm curious if there is a reliable way with the minis, or if you all think none of it is very accurate?