Oh my gosh, they look great! Mom and dad are taking great care of them! Once you start handling them, you should start weighing them every day, too, and track their weight. Once they are fully feathered, they will start to drop some weight in preparation to fledge. I would expect that between 7-10 weeks. Then they will leave the nest during the day and start to perch, then start to learn to fly. During that time, make sure they have access to all the same foods as the parents, but some in softer form (pellets soaked in juice, mashed veggies and fruits, cheerios). They will start by playing with the solid food, and start to accidentally eat it, too!
