child_secret_faith_conversion_critical_failure_effect

child_secret_faith_conversion_critical_failure_effect = {
	hidden_effect = {
		# Save and reveal secret
		scope:guardian = {
			random_secret = {
				type = secret_crypto_religionist
				save_scope_as = guardian_secret_faith_secret
				if = {
					limit = { NOT = { is_known_by = scope:child } }
					reveal_to = scope:child
				}
			}
		}
		scope:child = {
			# Inform the child's liege if relevant
			if = {
				limit = {
					is_ruler = yes
					NOR = {
						liege = this
						liege ?= scope:guardian
					}
				}
				liege = {
					send_interface_message = {
						type = event_religious_neutral
						title = child_secret_faith_conversion_critical_failure_effect.liege.desc
						left_icon = scope:child
						right_icon = scope:guardian
						show_as_tooltip = {
							scope:guardian_secret_faith_secret = { expose_secret = scope:child }
							scope:child = {
								add_opinion = {
									target = scope:guardian
									modifier = hate_opinion
									opinion = -30
								}
							}
						}
					}
				}
			}
		}
	}
	scope:child = {
		# Inform the child
		send_interface_toast = {
			type = event_religious_neutral
			title = child_secret_faith_conversion_critical_failure_effect.desc
			left_icon = scope:child
			right_icon = scope:guardian
	 		scope:guardian_secret_faith_secret = { expose_secret = scope:child }
		 	add_opinion = {
				target = scope:guardian
				modifier = hate_opinion
				opinion = -30
			}
		}
	}
	scope:guardian = {
		if = {
			limit = { this = root }
			hidden_effect = {
				add_opinion = {
					target = scope:child
					modifier = hate_opinion
					opinion = -30
				}
			}
		}
		else = {
			add_opinion = {
				target = scope:child
				modifier = hate_opinion
				opinion = -30
			}
		}
	}
}

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