I’m almost new to the hobby. I say almost new because it’s been over 40 years since I had been around chickens. So I’m a bit rusty but not a total lost. I’ve been back around chickens since the end of June and I hatched my first chicks which were born July 23rd. Now from what I’ve been reading on the internet it’s says that a rooster can not fertilize eggs until between 4 to 6 months old. I’ve had the newbies mix with the older ones since about 2 months old. To my surprise on October 3rd I crack some eggs and found 3 that seemed to be fertilized and now again about 4 days ago. Remember they were born on July 23. I didn’t think this was possible. Any input on this would be appreciated.