Well it is a colourful day today! Both of these illustrators love bright colours and their books have great visual impact.
Demi, the pen name for Charlotte Dumaresq Hunt, comes from a very artistic family, married Tze-si Huang who was born in China, is a practising Buddhist and has travelled widely and studied many art techniques. In an interview she says, "Life is magic. Everything alive is magic. To capture life on paper is magic. To capture life on paper was the aim of Chinese painters. That is my aim too." Demi has a love also of gold leaf and intricate detail which she also includes in her illustrations. Many of her early books are retellings of folktales. See The Empty Pot, Firebird and One Grain of Rice. Her more recent books present important figures in history and /or religion, such as Gandhi, Buddha, Muhammad, and Mother Teresa.
Ellen Stoll Walsh, on the other hand, makes books for much younger children. They have less text and more gentle illustrations, which use torn paper collage in the style of Leo Lionni. She uses mice and other small animals as her characters. She is probably best-known for her series of concept books which feature a very attractive mouse family, Mouse Paint; Mouse Shapes and Mouse Count. Many teachers use Mouse Paint, together with Lionni's Little Blue and Little Yellow to introduce the colour wheel and mixing colours. I was very interested to read that Ellen was reading a Lionni title to her son, when she had the thought that she would like to make children's books too.