First, it was Leia, then it was Jodie. Both times, when Olivia thought she had grasped the truth, she was wrong.
Jeff didn't know what had happened. His memories stopped a few years ago.
"Olivia, do you have so little faith in me? If I wanted a baby, I would've married her and asked for your permission. I'd only have a baby with her if all the conditions were right. I'd never take having a baby so lightly."
If Jeff hadn't told her, Olivia would have held onto the misunderstanding forever.