5th Sim not showing in toggle bar

So I recently made a household that houses 5 sims, but for some reason I can't toggle to the 5th sim in the household. It doesn't show up on the toggle bar at all. I know you can have up to at least 8 in a household but I'm not sure why mine's not working (this is the first time I'm making a household bigger than 4). The 5th sim in the household shows on my screen in the household but not on the toggle bar so I can't switch to it. And once I exit the game and reopen it, the sim suddenly isn't a part of the household anymore (and I save my games every time). Not sure if I'm doing something wrong or if I just really don't know how to play sims lol 

Any advice or help would be great, thanks!