[Petit Suisse]

That's great. The bonus is a bonus for a reason I suppose, but in terms of the logic of how to do it, think of it this way...

You have already asked the user if they want to repeat the program, and if they input "yes" your while loop continues.

In the bonus you want to give them an option so they can input EITHER yes OR YES OR Yes.

In the same place you defined "while statement true", you can pick "logic". This will give you the option to add criteria, such as either yourVariable == yes or yourVariable == Yes or yourVariable == YES.

Have a play with the logic option and see how it goes. There might be other ways, but that way worked for me.

Good luck playing!