Last year I started a portrait on a larger than my usual size canvas. I left it for several reasons. Colours, Bad likeness, bad composition and bad painting. I had not used the whole surface of the canvas so there was large boring areas.
I find that the easiest way to make an image more interesting is to simply add another person. And if they happen to be sisters there will be interaction. It is inevitable. So I asked my two daughters to sit in the chair already used in the painting and my oldest to try to get into the original position so I could use the original portrait as much as possible. I took a series of images and they managed to go from laughter to crying and back to laughter in five minutes. Firstly I thought I had nothing to use as they were mostly fooling around but then there was this wonderful image of older sister trying to deliver whilst controling unhappy sibling. There was lots of hands and arms all over the place which I felt gave a sense of motion.
The final result.