I have 5 Black Sex-Link hens. They were 6 months old this past Saturday. One of them has been laying regularly for about 3 and a half weeks. She is the ONLY ONE laying! All of them have nice, red combs. They are all very healthy. I recently checked all of their vents to make sure there were no problems. Am I too anxious? I was told they should start laying by 5 or 6 months and yet still only 1 egg a day. I will say that although the temps have been cooler over the past 4 or 5 days, we did have some hot ones in the middle part of this month. Any advice? Here is a picture of my layer.