@SJWmama Could you try a save without changing the age settings ? I'm guessing that's the cause. you're essentially taking days away if you change from long to short so it's their birthday earlier as anticipated and they just age up.
I had this occur with one of my sims. Life span was short from the beginning of the save (settings changed in previous save files). He was a premade sim, Tomax Colette from RoM. Previous day, he had the "1 day until age up" in the age bar. He woke up at 6am to age up from young adult to adult, followed by a sad moodlet for the missed birthday. Most of the sims I've been playing with seem to be able to get to their birthday cake, but since it happened, I've also been making birthday cakes for a birthday breakfast. XD
@crinrict Correct
New reply to add I just had a newborn age up to a toddler at 7:55am, also on short life span.
