you won’t be able to get it saved as a state but you can just search for the data or save it on another data to access it. bubble will return it as soon as it is created which will be fairly instantly.
when you create the data add the parents data to it so you can search for it on the page
ie the page has data “reservation” therefore write that reservation to each guest and then on the page just search for guests with the reservation (or add the guest to the reservation as a list)