The moment when Spencer James fell in love with Olivia Baker

The moment that this all happened was after Spencer got shot. That is when they started spending nights together hanging out. When he got to Beverly he was attracted to both Layla and Olivia. In Ep 4, he started seeing Liv as more than a friend for a second but Jordan's theory made Olivia pull back so he gravitated towards Layla because Layla was there and was giving him her time (even though she was in a relationship at the time). And after he got with Layla the door with Olivia was closed and they just became best friend.

There is a shift that happened after he got shot. They started hanging out more than they were before and once summer hit and everyone was going on trips, they got to spend all their time together. He knew he loved her when he took three buses to go see her in Beverly (2x16) but It hadn't hit him yet. That's why when he got to vegas, he was conflicted because Layla wanted him back but like he said "something felt off" and he felt like he would rather spend his time with Liv. Him barely going one night without liv in vegas wasn't his first realization but it was one that was in his face and then everything happened when she actually pulled up to Vegas.

That summer, those pre-existing feelings grew a lot deeper when they spent so much alone time together, in a way that hadn’t really done before. When Spencer first moves to Beverly, he’s instantly attracted to Layla, but there’s also a spark between him and Liv, and they’re spending more time together. When he becomes friends with the football team and starts dating Layla, him and Liv don’t really hang out one-on-one that much anymore- Layla (or someone else) is usually there. So that spark isn’t really able to go anywhere. But as soon as they really get a significant amount of alone time, it’s game over. He’s in deep lol.