We are getting our first chicks tomorrow, but we can only get two. In about 3 weeks, we can get another one (as the varieties we want come available at the local farm). Then two more in another week, and so on until we end up with about 7, adding the last chicks around mid march to early April. Can we just add two day old baby chicks to a box with say 2, 3, or 5 or 6 week olds? This sounds like it may be trouble. And how long can I expect say a standard size to raise from two day old to big enough to release in the outdoor coop?