Has this file passed the mypy type checker?

I've added type annotations and fix the bugs to ensure the file passes mypy type checker.

Can you describe the difference and any dis/advantage of using a class method vs a function?

A function is standalone code with its own behaviour, while a class method is code whose behaviour belongs to an object or class and operates on its internal state.

------Advantages of using methods: ---------
• Ease of documentation and discoverability
Attaching behaviour to a type makes it easier to find and understand all operations related to that type. For example, methods on str or Person group related functionality together, rather than scattering it across separate functions.
• Encapsulation
Methods hide the internal representation of a type. If the implementation of Person changes (e.g. storing a date of birth instead of an age), the code that uses Person does not need to change, and it is clearer which methods may need updating internally.
• Improved readability
Methods read like natural language and make code easier to understand e.g is_adult(Imran)

Can this print grandchildren recursively?

I've now fix my code and family tree prints children recursively. Thank you for your review and feedback

I think you have an extra bracket here you dont need

Thanks for catching that. I've now fixed the output message formatting by removing the extra parenthesis.