I finally found my motivation for a crafting project that I have been mentally kicking around for many months. I used this tutorial.
The most difficult part was resizing the originals to ensure they were the same sizes when printed (and simultaneously realizing what an idiot I was for not thinking about the fact that because Kid 1 is four years older than Kid 2, her head might be a wee bit bigger than his.)
(Then again - LOOK AT THE SIZE OF HIS NOGGIN!!)
I am so in love with the final product.