Well, at first, they would probably be overjoyed and their relationship would be filled with excitement. But as the pregnancy progresses, stress could set in. Maybe they would start to argue more about things like baby names, nursery designs, or how to raise the child. However, overall, the shared experience of the pregnancy would most likely strengthen their bond. They would have to make decisions together, like choosing a doctor, and this would bring them closer in the long run. Also, they would have to support each other through any pregnancy - related scares or difficulties.
One possible fanfiction could be about Liam and Annie's secret adventure. They might decide to run away from the drama in 90210 for a day and explore a nearby abandoned place. Along the way, they could discover old secrets about the town and also deepen their relationship as they rely on each other in this unplanned journey.
There could be a kind-hearted truck driver who gives Riley a ride on part of the journey to Minnesota. This character could offer some words of wisdom to Riley during the trip.
One idea could be that Annie and Riley start a business together in the 90210 setting. They might face challenges like getting investors and dealing with competition, but their friendship helps them through.