military_order_yearly_trait_gain_effect

military_order_yearly_trait_gain_effect = {
	#Lazarites might gain a little leprosy...
	if = {
		limit = {
			primary_title = title:d_knights_of_st_lazarus
		}
		random = {
			chance = 10
			if = {
				limit = {
					NOT = { has_trait = leper }
				}
				add_to_list = lazarists
			}
			every_courtier = {
				limit = {
					NOT = { has_trait = leper }
				}
			}
			random_in_list = {
				list = lazarists
				add_trait = leper
			}
		}
	}
	#Hospital orders gain physician trait XP
	if = {
		limit = {
			primary_title = {
				OR = {
					this = title:d_knights_of_st_lazarus
					this = title:d_knights_hospitaller
					this = title:d_knights_of_the_tau
				}
			}
		}
		every_courtier = {
			limit = {
				has_trait = lifestyle_physician
			}
			add_trait_xp = {
				trait = lifestyle_physician
				value = { 1 10 }
			}
		}
		random = {
			chance = 50
			ordered_courtier = {
				order_by = learning
				limit = {
					NOT = {
						has_trait = lifestyle_physician
					}
				}
				add_trait = lifestyle_physician
			}
		}
	}
}

As written in game/common/scripted_effects/00_holy_order_effects.txt.