For #2, no they don't have to go... but the game add the stupid "never went to college" memory and makes your newly turned adult sim cry over that for a while. :?
And for #1, I do believe the child will still age. I think that option on InSim is set for the individual sims only, so if you don't want the child to age, you'll have to do the same for them as you did for the adults.
