YOu can honestly not tell till a Doodle is closer to a year of age what type coat it will get. But by 12 weeks if its is still straight I doubt it will be wavy as a adult. My pups are all wavy at 5 weeks of age.
Ours is a mini goldendoodle, bred from a goldendoodle and miniature poodle. Wavy hair as a small pup, but by 4 to 6 months very fine curls!! When it grows out it looks like dred locks?