...speaking of birthday discounts, Joe's Farm Grill in Gilbert (I've talked about them before, but they're worth another mention) offers $10 off your meal on your birthday. This means a burger with fries and half a milkshake...you have to pay for the other half. :)
They have the yummiest burgers, and all of the ingredients are locally grown. Plus, the property is so family friendly: open with lots of grass, big leafy trees for shade, and picnic tables for you to enjoy.
If it impresses you, Joe's is on Food Network Guy Fieri's top 5 list of Diners and Dives in the U.S. He recommends the Fontina Burger (which is good) and the onion rings (which are excellent).
Also, the Coffee Shop next door has excellent cupcakes...if you even have room for dessert.