7 year old grown?

Yes this is normal geldings do not tend to fullly mature until 7 whereas mares and stallions mature around 4. This changes horse to horse it has something to do with them being cut when they are younger :)
 
The testosterone in stallions encourages the growth plates to close more quickly so geldings may well be bigger.

I was always told that cobs didn't finish growing til they were 7. My lad was 5 when I got him and is 2 inches bigger 2 years later-also a cob. Don't forget to take widthways into account, too. Because he wasn't much worked when I got him, he filled out sideways once in regular work so his rugs went from 5'6 to 6'3 in under 2 years!
 
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