A Gargoyle's Life-cycle, According to Allegra, as Used in Her Fanfiction, "Adelpha" and "The Secret of Bain Felix":

I thought it might be a good idea to provide this timeline for readers, in case it doesn't correspond with other timelines that may be out there and might cause confusion. If you aren't really confused or curious when reading my stories, reading this appendix may seem like a boring "overshare". Sorry. Feel free to ignore.

Going forward, there will be some discussion of gargoyle mating and family life. Since the only information we are given in the show is that gargoyles age around half the speed of humans and it seems that the clan goes a pretty long time without having any babies, then suddenly produces a whole clutch of eggs at once, I had to invent a more detailed life-cycle timeline in order for my stories to make sense. It has come to my attention that there exist sources outside of the TV show itself which are considered "canon", but I haven't seen any of them, so this is what I've put together in my head, based on inferences made from the limited information in the show.

For the purpose of my stories, Gargoyles measure their lifespans in 7-year cycles rather than yearly cycles, beginning with each rookery summer.

*Conception to 7 Years- Infant gargoyles are within their egg for a year, then hatch and become nurslings. They are kept warm and safe in the rookery, even during the day, because they are too easily shattered.

*7-14 Years -Hatchling- They still sleep in the rookery, but venture out to play. This is the age of the trio when Demona begins to teach them and Goliath becomes second in command.

*14-21 Years- Page- At this age, they now have to sleep in the sunlight in order to heal and grow. Early training includes learning to glide, hunt, and other survival skills. Demona was this age when she became apprenticed to the archmage. The trio was near the end of this age when the Bad Winter happened in "Adelpha".

*21-28 Years- Youth- Training mostly includes combat and otherwise preparing to be warriors, healers, or other roles important to the survival of the clan.

*28-35 Years- Young Adult-They are now considered full warriors and adults in the clan. They can choose a mate at this point, though most do not until later. Goliath and Demona are mated at this age. Goliath officially becomes second in command at some point during this age. The trio were at this age when the castle was sacked.

*35-42 Years-This phase is more early adulthood. Gargoyles typically get used to their role in the clan as an adult and choose their mates. Goliath and Demona are at the end of this age when the Bad Winter happens. Angela joins the clan about halfway through this age. The trio were at this age through most of the original series.

*42-49 Years- First rookery. Females ovulate for the first time on their 42nd summer and only do so every seven years. They can ovulate multiple times during the same summer if their health allows, and can produce 1 hatchling each time, but only one or two is common. It's possible that Goliath and Demona bore children at this age that would have been killed during the massacre, but it's also possible that Demona and the other females in the clan did not ovulate properly because of the starvation they endured during the Bad Winter and there were no children born to the clan that cycle. Anyway, Goliath becomes leader of the clan during this age. Angela, Ophelia, and the lost trio are about to begin this age when "Secret of Bain Felix" begins.

*49-56 Years- Second rookery, Demona conceived Angela at this age, and the castle was sacked shortly after her egg was born.

*56-82 Years- Female gargoyles continue ovulating every seven summers, for seven rookery seasons, after which, they are typically baren. After reaching this age, both male and female gargoyles are considered clan elders.