wet_nurse_validity_trigger

wet_nurse_validity_trigger = {
	base_court_position_validity_trigger = { EMPLOYER = $EMPLOYER$ }
	is_playable_character = no
	is_female = yes
	custom_tooltip = {
		text = wet_nurse_age_tt
		effective_age < 46
	}
	custom_tooltip = {
		text = NONE_IS_NOT_CLOSE_FAMILY_OF_CHARACTER_COURT_POSITION
		NOT = { is_close_family_of = $EMPLOYER$ }
	}
	custom_tooltip = {
		text = none_has_no_particular_noble_roots_trigger
		has_no_particular_noble_roots_trigger = yes
	}
	custom_tooltip = {
		text = none_does_not_have_a_full_time_job
		trigger_if = {
			limit = { NOT = { has_court_position = wet_nurse_court_position } }
			court_position_does_not_already_have_a_job_trigger = yes # This positions is considered a job, and cannot be held at the same time as another similar position
		}
	}
	# Nuns cannot be wet nurses
	NOT = { has_trait = devoted }
}

As written in game/common/scripted_triggers/00_court_position_triggers.txt.