i think this post gives me an idea:
what if kerbals history are like shown on Prometheus, Alien, and Convenant movies?
probably a race that comes from laythe was trying to make life in duna and in eve?, after that the eve's life killed themselves causing high amounts of the eve's purple material, getting eve to its actual state, and in a war the dunatians killed themselves making duna a red ball made of radiactive waste that are too old for making radiation, and then the laythians seen that and tryed to make life on kerbin, then they seen that kerbals was the correct life types, so they (laythians) try to make a new substance similar to the kerbals original substance for improve themselves, and then they discovered that it was dangerous and the laythians was killed by its own experimaent.
some laythians escaped to tylo where they made an hiden base where they live actually out of the sight of kerbals.
probably any day, a kerbal will discover its base and kerbals will see the last laythian and this kerbal will contaminate and put in danger zone to the kerbal race.
now that i think it's a good idea for a new serie of matt lowne