Now that is interesting, cause I did age my child sim up as a toddler to see what she'd look like when she got older and aged her back down. I'll make sure not to do that anymore (oh, man, is that going to be hard).
I agree, very frustrating! In this save, I'm playing an Ultimate Sim challenge... it will continue on for 20 generations, at the end of which I will have to bring everyone back from the dead and make them young again. I have to have a child each generation, and it would really stink to lose one or the family to this glitch.