Some friends of ours have 4-6 hens and are going on vacation. They asked my parents to keep the 4-6 with their flock (about 30) while they are away. We always introduce new birds by keeping them close but seperate while they are getting used to each other, so my initial response was to advise my parents not to dump a few new hens into an existing flock. Is the introductory period necessary? I need some advice, we are new to chickens as of last year, and my parents even newer. My mom is wondering what to do??