Wash and colored pencil portrait

I drew this portrait of my son and his girlfriend as a Christmas gift for them. I first sketched them loosely with graphite pencil on plain white paper. I felt I got a good likeness of both Tom and Brooke, but Brooke’s hair is a distinct and pretty red color, and I knew it would look more like her if I did it in color. So as not to lose the good drawing underneath, I scanned the pencil sketch and printed it onto a ruddy toned Mi-Teintes pastel paper. Then I put thin washes of acrylic color in the hair and clothes, keeping them not too wet so they would not buckle the paper.  Finally I went back in with white prisma pencil to put some highlights on the skin tones and background, and draw in some details and emphasize some lines of the sketch that got a bit lost and blurred from applying the washes. I tried to keep these succeeding steps loose too, to give the whole piece a fresh sketchy quality.