We've got 2 white leghorn hens (egg farm rescues) that we've had for over a year and some production red hens that we raised from chicks. Today, one of the leghorn hens started crowing! I've heard that rarely a hen will start doing that in the absence of a rooster, but we've got a quite randy Production Red rooster who seems to keep our 8 hens happy or at least busy. Any ideas???