Not rare it never-
-happens. Epiphyses close @ different times throughout the body
, as well as depending on male or female
It is driven by genetics. People are getting bigger over the years. Go 2 the ship in the harbor museum in Boston & tour it,. You can't stand up & won't fit in the bunks they slept in. You can Google this,. There are tables with the age range 4 male & female.