I grew up an only child*, which meant I had to be more creative than other kids.
For instance, I loved playing Monopoly, so spent many a rainy afternoon competing against myself. I would move from one side of the table to the other, rolling the dice and moving around the board, buying properties and charging rent to myself. I even borrowed from myself when, for instance, my race-car-man ran out of money and my top-hat-man was demanding rent. Borrowing added a new dimension to the game; I was able to prolong a game for days. It's really surprising that I didn't become an accountant, considering the complicated record-keeping I had to do for each of those Linda vs. Linda marathon Monopoly games.
When it came to creativity, though, my magnum opus was the imaginary family I had for a couple of years. In that family, I was one of twelve children, including two sets of twins. Each season, when we received our new Sears & Roebuck and Montgomery Ward catalogs, I would lay claim to the old catalogs and cut out head-and-shoulder pictures of my "brothers and sisters." I then glued each of them to a wallet-sized piece of poster board, thereby creating a complete set of current family photos! It delighted me that some of the fashion models conveniently showed up season after season, so I could actually use the same ones for the same siblings, and watch them "grow up." I kept my imaginary brothers and sisters very private; I don't think even my mom knew about them. But one day, years later, when my two sons were squabbling about something, I decided it was the right time to share with them the story of my imaginary family, in the hope of encouraging brotherly appreciation. What a mistake! The lesson was totally lost on them, as they broke out in robust laughter. To this day, at the most unexpected moments, one of them (I guess that would usually be Tim) will mention my "catalog family," and provoke yet another round of merriment at Mom's expense. (But I know you both love me!)
[* I was not always an only child. My little brother, Bobby, four years younger than I, died when I was seven years old. ]