Yes, you can do it as many times as you have Sims. I often have a large household and I'll have an individual car assigned to each parent and all the teenagers.
Your Sims must have a huge carbon footprint lol!
Anyway, things I'd like to see...
- I'd like more baby/toddler/child interactions. I love Sim children, but I wish they had more to do because sometimes I find it boring to repeat the same routine, especially with the babies-I wish I could fulfil their social need with more than just snuggle; maybe it would be nice if an adult or teen sim could sing them a lullaby, play a game with them or something
- echoing what someone further upthread has said: It would be nice if teen Sims could flirt with young adult Sims; alternatively if two teen Sims are seeing one another when one ages up to YA it'd be nife if the relationship could carry on
- a hot tub; also public woohoos. I loved it when Sims could woohoo in a photo booth or in the dressing rooms out shopping
- pets: cats, dogs, horses, birds (not just parrots - canaries, budgies, doves, pigeons [you could have Jack Duckworth from Coronation Street in the Sims!] etc), reptiles, rabbits and rodents. It would be nice if you could give them traits rather than the old friendly/unfriendly, intelligent/dopey and brave/cowardly markers. I always ended in Create A Pet making friendly, brave, intelligent pets. I didn't have the patience to train dopey ones...
- more careers such as education or maybe one of the more offbeat ones such as Slacker or Psychic. The idea for a branching education career posted above sounds brilliant
- more furniture and toys for babies, toddlers, children and teens. A single bed for teens or children that can compete with the highest double bed comfort rating would be nice - just because they sleep alone doesn't mean they don't deserve the best sleep money can buy! The poster aping The Breakfast Club tickles me and it always goes up on the walls of my teen sims rooms. A changing table and more places for babies/toddlers to sleep would be nice; I'd like to have a proper nursery furniture set(s)