Its little surprise treats DLP might (emphasis on the might ~ absolutely no guarantees) give you if you are staying onsite and let them know in advance of any special birthday or celebration you will be having during your trip.
things like room upgrade or VIP breakfast pass, or tea basket or cuddly toy/choc coins etc left for you in your room in arrival, that kind of thing.
whether you get any of this pixie dust is entirely down to DLP staff discretion.