They're on aspen at the moment, just because I'm finishing up the bag I've got. But they may have been on pine at the pet store.. I did see that they were in wood shavings, I'm just not sure which kind. Luckily it's not the pregnant one that's sneezing, it's her cage mate. Would you say the best course of action would be to just monitor them both for now then? In the meantime, I'm assuming hold off on breeding them..?