```mermaid sequenceDiagram participant Alice participant Bob participant John Alice->>John: Hello, John! John->>Alice: Hi, Alice! How are you? John->>Bob: Hi, Bob! How are you? Bob->>John: I'm good, thanks. John->>Alice: I'm doing well, thanks. Alice->>John: I'm fine, thanks. John->>Bob: I'm doing great, thanks. Bob->>John: I'm doing well, thanks. ```