From my observations, they're social animals, though not remotely to the degree of dogs or similar animal, but definitely more than ball pythons. If they're both boys and getting along fine, I wouldn't separate unless you see signs of aggression -- it's not likely to be an all of a sudden sort of thing. If they're a pair, then you probably have a couple of months before too-early mating is likely, but it is true you don't want to end up with a worn-out calcium-crashed young gecko.