Odd No-Start

I had an odd experience starting my Prius yesterday. It has Smart Start. I took my daughter to a voice lesson and sat out outside to read in the car. I turned off the car and sat for a few minutes. Then I was a little cold, so I turned the car back on, backed down the driveway to a sunny spot and turned the car off. About 30 minutes later my daugher came out and got into the car. When I hit the power button, all I got was the security icon. I made sure my foot was on the brake and tried again, still just the security icon. I tried opening and closing the driver door and still had no luck. All this time my fob in my purse, sitting on the floor by my feet. It hadn't been moved since I started the trip. Finally I got the fob out of the purse, held it up so the car could "see" it, and hit the power button. It started right up. Anyone else have anything like this happen?