Zack decides to have a bit of fun with his life, and decides that he has always wanted a twin, but he also has always wanted to be the oldest.
"Benjamin is in the room with me," Zack says, an idea forming in his mind. Ben appears in his room and begins talking with Zack, oblivious to the fact that Zack is talking, too.
"Benjamin is my twin, and he was born 5 minutes after me." Ben begins to shrink and his features begin to change, and in a few moments, Zack is looking at a mirror image of himself.
Then Zack makes the final change: "Benjamin is a girl, and her name is now Brenda."
Ben, now Brenda, begins to change again, all the while oblivious to the changes going ob around her. When the changes finish, Brenda is a cute teenage girl that has very similar features to Zack. As the changes finish, Zack feels his memories flow into new ones, in which Benjamin is now his kind sister Brenda.
Now that Zack has perfected his family, he begins to get an idea of what to do next: