It's just The Sims, not SimCity that you are referencing. There are 3 different games, The Sims, The Sims 2, and The Sims 3 with all sorts of add-on packages that you can purchase. Facebook now allows you to play The Sims through their games like Farmville. Yes, in either of these Sims games, you can "kill" off anyone you want too. You can put a character in a swimming pool to swim, remove the ladder and the Sim will die. Once the Sim dies, the grim reaper will appear and offer you the opportunity to resurrect your Sim. There are many ways to kill of a Sim. Starvation is one way, allowing them to live in filthy surroundings is one way, starting a fire in a kitchen is yet another. I'm sure since the last time I've played, people have become more and more creative with ways to kill Sims off. You can also have your children removed from your care if you are neglectful, etc. "Social services" will arrive at your home and take the children from you.
Anyway, don't ask me how but I don't see Julia as being one to sit for hours to play games with her OCD.