Photos to LG tv

[tat4bob]

I have a gs3 that i got laundry check weekend. My girlfriend has a gs3 that she got in approximately Oct or Nov. I just got a brand new LG 55la7400 tv. When I view my gallery on my gs3 a small icon appears I love the upper right hand corner with a '1' in it. When I click on it, it shares the images from my gallery on the new 55 inch tv which is awesome. For some reason, when I do the same with my girlfriends gs3 also on att, this option is is not available. How do I get this feature active on her model which is a more recent model? Is this an app or something in the settings? Any help would be greatly appreciated.