I am going to be going to my grandmother's house this weekend for her anual "June Birthdays" celebration. I want to make a cake, but I am not sure how to incorporate every one in it. Does anyone have any ideas? I though about doing a standing tree, like standingforjesus's cake, but is that too much like a reunion cake? I am just not sure.

How about a summer theme -with everyone joining in? Like a pool party with everyone in the pool?

I agree with summer theme. Especially being for June birthdays...I like the pool idea or what about a beach theme?

You could look at stickers and birthday cards for inspiration. I have some stickers that are "month" themed. If I need to do a cake for a group, I just pick the appropriate month and go with that.