In fact when I got the sims3, I made a Brandi, because I was going to recreate the scenerio from the sims2. She had two boys and was pregnant and supposedly her husband had either left town or something, but his name was Skip Broke (I think, could be wrong, but it was a Broke that is still in the sims3) and he is a child in sims3, so I finally got it to the point of Brandi and this Broke kid to teenagers, maybe she remembered him, haha, but could not get them past friends, they would kiss and all that would come up was, Brandi thought he was ok, no flirty, no alluring, nothing. Even as adults she did not like him romantically. I thought that was interesting, so I experimented on another sim and she fell for him immediatly. Maybe they do have a memory, lol or so that is what it seemed like anyway. I guess in the game we can think what we want or let our imagination go wild.
In answer to your question though, that would be a good idea, there are some first time simmers on here that might be interested in the history of some of the sims in the game that go back to sims1.