1,435. From a Katan to a Gadol

Hilchos Ishus 2:10

A boy from birth until 13 years of age is called a katan or a tinok (i.e., a minor). Even if he grows several pubic hairs grow in this time, it is of no significance, like hairs that grow from a mole. If he grows two pubic hairs after reaching the age of 13 years and one day, he is considered a gadol or an ish (i.e., an adult).

Hilchos Ishus 2:11

If a boy reaches the age of 13 without growing two pubic hairs, he is still considered a minor until he is within 30 days of his twentieth birthday; this is so even if he doesn’t exhibit the signs of infertility. If he reaches 30 days of his twentieth birthday and has grown neither pubic hair nor facial hair, then if he exhibits one of the signs of infertility, he is considered a saris (congenitally infertile) and a full adult. If he does not exhibit any signs of infertility, then he is considered a minor until he grows two pubic hairs or he reaches the age of 35 years and a day.