How do I print photos from Facebook?

My Son posted pictures of the Grand kids on Facebook and I wanted to print one of the Granddaughter. When I attempted to do so instead of the picture of her getting printed in printed the entire post from my Son, including all the words and ect. When I clicked on her picture it filled most of the screen with nothing else on it, then when I clicked print all the other things printed with just a little thumb nail type picture of her. Is there some way of just printing pictures only?