Here's an infographic I drew a few months ago on the reproductive cycles of Avelevians.
While the exact social structure varies from culture to culture, Avelevians typically have a pseudo-eusocial family structure, living with their siblings in groups of 5-10. Generally, only one member of the sibling group will engage in courtship at a time.
Female Avelevians will lay one large egg at a time. This egg contains a single haploid cell, which splits into 5-10 cells before undergoing external fertilisation from a male. The embryos then develop in the egg together, hatching after about 40 days.
Because of the way the haploid cells split, siblings that come from the same egg will on average share 75% of their DNA with each other, and because they have a ZW sex determination system, they will all be the same biological sex.
Hatchlings are usually raised through the cooperation of their parental sibling groups. It takes about a year for the young to develop from fully aquatic tadpoles to semi-aquatic adolescents. Once their lungs have fully developed, their tails slowly begin to atrophy over a period of about 2 years, but they don't reach sexual maturity until they're about 12-15 years old.













