Sim ages on travelling to the future

[Sim2000]

Hi, I don't know if i'm posting this in the right place because i'm new to this whole thing but i have a problem with travelling to the future every time i travel to the future one of my sims always turns into an elder, when he left his home as a young adult but it doesn't happen to any of the other sims, can anyone help o'r suggest anything? 

[Lisa46]

Make a thread on the into the future board to post that.