I need some help from all the good cake designers in this site!

I just received an order for Nov 24 for a milestone cake. This is to represent 4 birthdays within 1 month. husband 50, and children: 21, 18, 16. I have to incorporate all birthdays into one cake....HOW???

I asked more information about the customer's family, waiting for her reply.
I can not visualize how this will be done. I do not want a complete design, just a possible way I can represent everybody in the cake. Without knowing personal details is very difficult.

Thanks,
Maddy

A square cake has 4 sides.

Pipe "Happy Birthday" on the top...decorate one side per person.