Sims still aging?

Hi,

I've recently bought the sims 4 on ps4. I found out about the sim auto aging setting and have changed my settings so only the active household for played sims ages and unplayed sims aging is turned off.

I was having no issues until I moved a young adult out of the family household into her own household. At first I thought I didn't create the new household correctly so I used to main menu and moved her across that way into the new house with another sim. She is pregnant and I played another household for 2 days. When I returned, she is now in the third trimester but before had only just discovered the pregnancy. Does anyone know how to fix this? The only other thing that has changed is that I added the sims cats and dogs expansion just before she moved out.

It's very annoying. I don't want to keep playing if it constantly affects all my other characters!;