How many sims can you handle at once in a household?

I answered 5 -- but I just dealt with a family with 3 kids and it was exhausting - the mother who had a full-time job just couldn't keep her energy level up, her husband was a slob, so there were dishes and piles everywhere... I can do 5, but if they are younger than teen, it's work! I'm hitting the pause button all the time.

I think 3 is my perfect "chill" number. Enough to keep things interesting not so many to be overwhelmed.