Art commissions are something I am trying to get into more. They're a good way to keep moving when one is stuck with "artist's block", and a unique collaborative experience. Recently, I finished up a piece (an illustration with pen and gouache) of actual little ones wandering through my vignettes - a group of five children (3 of them triplets). What a cool experience - the family sent me the following video of their children looking at the piece for the first time. They totally got it!
Have a look: http://vimeo.com/37499152