I did my best with trying to step up and make her a fun cake for her birthday. The bottom of the cake is an 8" cake with two layers, making it 4 inches tall. The middle, green part is a single 6 inch cake. The top was made by baking two cakes in thoroughly cleaned out tuna fish cans. I have used the tuna fish cans to make my kids little cakes that they could decorate and have all to themselves. They only require a small amount of baking time; I baked them for 15 minutes at 350 degrees. Of course, having such a small top layer gives the recipient their own personal cake, which is kind of fun.
I added a few personal touches, so it wasn't just a generic cake. The book is because my sister loves to read, the rock in the middle is a hearthstone from the game World of Warcraft that she plays, and the syringe on the bottom is because she does all sorts of labwork with blood at school. I realize a syringe is not used to draw blood....but it was the closest I could make and still have a recognizable object.