I came across a helpful tip when reading a book about writing screenplays. The Law of Threes. If you want to establish a developing relationship in your story, you need at least 3 situations where your characters interact. If a relationship builds too fast, your audience will think it’s contrived. Think of it as a 3rd date. The 1st date is a little awkward, the second date is a little more comfortable, but by the 3rd date, you’re starting to feel that this new relationship may be a reality.