Chapter 5 of the book “The Only Child Club” by Anne Fine is called “The Secret Meeting.” In this chapter, the main ideas are:

1. The Only Child Club: The main characters, Grace and Billy, have started a club called “The Only Child Club” because they both are only children. They want to meet other only children and have fun together.

2. The Secret Meeting: Grace and Billy plan a secret meeting for the club in their treehouse. They want to discuss ideas and make plans for future activities. They are excited about the meeting and hope that other only children will join them.

3. The Club’s Rules: Grace and Billy have come up with some rules for the club. They want everyone to be kind and respectful to each other. They also want to make sure that everyone gets a chance to speak and share their ideas.

4. The Club’s Activities: Grace and Billy brainstorm ideas for activities that the club can do together. They think about having picnics, playing games, and going on adventures. They want to make sure that everyone has fun and feels included.

5. The Club’s Invitation: Grace and Billy make invitations for the secret meeting and distribute them to other only children in their neighborhood. They hope that many children will come and join their club.

Overall, chapter 5 of “The Only Child Club” focuses on the excitement and anticipation of starting a club for only children. It highlights the importance of friendship, inclusivity, and having fun together.