If she already had Marcus, I guess you could read that to explain why Beth really didn't want her going to the beach party, yet Brooke still thought she was innocent. Really hard to believe that she got pregnant by Justin with Storm always hovering around... must have gotten it on in the bleachers at the gym, lol.
I knew that Bill was a retcon, but I'd never realized how adamant the writers were that Caroline was an ONLY child, and Bill Sr had NO ONE ELSE. I just thought he'd never been mentioned. How was Karen introduced then? She was a new character when I started watching. Bill had money and a stable marriage... how on earth did they just "lose" a twin? She wouldn't have been adopted out, surely.
Brooke going to the hospital was bad enough... I guess I could see a young girl getting starstruck and wanting to see celebs in person... but to actually go into Caroline's hospital room and talk to her... and for Caroline to be fine with it... really ridiculous. Maybe it played differently in the 80s before the privacy laws were expanded. Brooke is definitely stringing Dave along, wondering what life would have been like had her father made money... but you can sort of understand it, since she hasn't even graduated college yet and doesn't want to be tied down into a lifelong commitment. I really hated Brooke in the 90s and actually see her in a slightly more sympathetic light in these episodes, but the seeds are there.