Not finding the airplay icon/function on my iPad 3 to connect to Apple TV?

I have recently bought Apple Tv and my iPhone 4s and iPad 1 can connect to it via AirPlay no problem.

My daughter has just got an iPad 3 and for some reason the AirPlay icon doesn't appear anywhere so can't connect to Apple TV.

Is there only a certain number of devices that can connect to Apple TV or is the AirPlay icon somewhere else on the ipad3?

Home sharing is turned on and connected to same network as Apple TV.

Would be grateful of any assistance?

Thanks in advance!!!