Giantkin

Giants of Beltiar

As the mana of the world became unstable in the time before and after the Cataclysm, an odd thing began happening to the Giant races of Beltiar. In ever-increasing numbers, their young were born small and never grew to their full height. Some of the tribes, especially the Hill Giants of the south and the Frost Giants of the frozen north killed these runts.
Eventually they stopped doing this and exiled them instead. The smaller giantkin formed their own tribes and villages and eventually began to come into contact with the Post-Cataclysm survivors of Beltiar. At first, these encounters were more hostile than not but over time, these new "giants" were accepted by their neighbors. Some even allied against their former kinsmen.
Stone giants gave birth to the Goliath race but had little to do with their smaller, weaker offspring. Hill Giants gave birth to Ogres and though smaller than their parents, they were also savage and happy to serve them. The tribes of Forest giants in the wooded areas in the north dwindled and disappeared mysteriously, leaving behind the mostly peaceful Firbolg tribes. Frost Giants gave birth to the Icemen berserkers who built ships and raided the coastal areas up and down the Iceknife Strait.
There are no documented cases of smaller racial variants for any other Giant Races. However, the Storm Giants, Cloud Giants, and Fire Giants are never seen among the mainland population so there could be a similar phenomenon occuring in their settlements. Only time will tell.