Speed Up the Aging Process!

I'm probably super late on this but I found a way to speed up a Sim's age. Once the first generation parents moved out of the house, I had to vacant spots. I had 2 daughters that were already in the child stage. When I clicked on the portrait, the gave me the option to create or promote and I chose promote. I don't know what possess me to do that. But when I did my daughters started jumping up and down all eager. I chose one and she turned into an adult instantly.