activity_try_find_new_host_effect

activity_try_find_new_host_effect = {
	# Make the title heir the new host
	if = {
		limit = { exists = scope:host.primary_title.current_heir }
		scope:host.primary_title.current_heir = { save_scope_as = new_host }
	}
	# Otherwise pass to primary heir
	else = {
		scope:host.primary_heir ?= { save_scope_as = new_host }
	}
	if = {
		limit = { exists = scope:new_host }
		#Also inherit the travel plan
		if = {
			limit = {
				scope:host.current_travel_plan ?= {
					any_entourage_character = { this = scope:new_host }
				}
			}
			scope:host.current_travel_plan = { set_travel_plan_owner = scope:new_host }
		}
	}
}

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