My party of adventurers have fought two black dragon wyrmlings now, for two different reasons, because of two different modules, maybe the authors from WoTC really dig the Dragon half of the game's name.

Both of them could flee, and fled, so I was trying to plot a "revenge" arc form both dragons to cause havoc in the world when they are powerful enough. However, according to the SRD, it would take around 96 years for them to be adults, and my fighters would be retired by then, if not dead way before.

So, what I ask is: Is there any "official" way to pull this off without waiting all that time? Any solution from any source that can make monsters grow older would be good. Or would I have to make something up?