We introduced our 7/8 week pullets in with our flock because we had a surprise cold snap and I wanted to make sure the young ones were warm enough. They have been in a separate coop and run next to the main coop. We placed them in at night and the adults are tolerant at night time. During the day the 2 chicks stay together and the rest of the flock goes off and do their own thing. About what age will they start moving with the rest of the flock?