We stayed at All Star Sports last July. My son turned 9 on our 5th day of vacation. I had it noted on our reservation. I also made up mousekeeping envelopes for each day of our trip, and made a note on each one about his birthday coming up. We got towel animals every day but his birthday. On that day we came back to the room and found balloons and a card from Mickey and Minnie.
I called the desk the night before and requested a Goofy birthday call as our wake up call. I made him answer it, but he was half asleep and didn't remember. At Epcot the Canadian cm made the call for us, so he did get to hear it.
We had been to all 4 parks by then, and had gotten the 4 birthday buttons. I ordered him a customized birthday shirt off Ebay, and put all 4 pins on him. Everyone stopped and told him happy birthday.
And I highly recommend the Garden Grill in Epcot for a birthday meal. Character interaction was great, and we got a birthday cake for no extra charge (just didn't get the regular dessert). The cake and a card signed by Chip, Dale, Mickey, and Pluto were delivered by Dale.