Welcome Back Hilary!
Here is a confession - I often get so caught up helping others plan their Disney vacations that I forget to make Advanced Dining Reservations (ADRs) for my trips. In fact I finally made some today for a trip that I've had planned for months that's now only a couple a weeks away.
Its always disappointing to try to get ADRs at a dining location only to find that they are booked. Don't lose hope just yet. It may still be possible for you to still get in. Keep trying by:
* Calling 407-WDW-DINE every few days as Guests often cancel reservations once they get closer to their trips and firm up their plans.
* Continuing to check for
reservations online for 'Ohana.
Be sure to continue to check even after you arrive on property if you haven't had any success before you arrive.
You may want to consider dining at other locations where Mickey appears which would give you more opportunities at getting reservations. Even though they aren't as convenient, Chef Mickey's and Mickey's Backyard BBQ are options.
You can indeed try walking up and ask. We've done this at several locations and have often had good success. They start serving breakfast at 'Ohana at 7:30 a.m. and I'd suggest going as early as possible. That will give you the best opportunity for a wider range of times to get in. Take something to keep your son entertained and be prepared to wait a bit just in case. I'd also be sure they see that your son is wearing his "Happy Birthday" button. Maybe that will give them more incentive to send a little pixie dust your way. I'll keep my fingers crossed for you!
Please feel free to visit with any other questions. I'm hEAR to help!
Wishing your son minnie magical birthday memories :-) Allison V.