Boil the chicken breasts in enough water to cover in a saucepan until cooked through. Cool and cut into bite-size pieces. Combine the chicken, eggs, grapes and celery in a large bowl and mix well. Stir in a mixtureof the mayonnaise and sour cream. Chill, covered, until serving time. Stir in almonds just before serving. Serve on croissants or sliced bread!!! Enjoy!!!