What settings are you using?
You have 2 options to help you focus:
-You can change your AF to quick focus (you have to go through the menu and figure it out). After that every time you're filming - press the shutter button and it will focus. Two things to remember when you're doing this, you can not be recording (red LED light) when you're trying to quick focus. So select a subject (in your video, the subject was the cat), point your camera to the cat and press the shutter button to focus, and after it was in focus, then and only then you press record. The other thing to remember is that you have to have the lens in AF mode, sometimes I put the lens in MF mode (a little switch on the side of the lens) and forget when I try to quick focus.
-The other option is through manual focus (MF), if you want to be a good videographer/photographer... you need to master this... because you will be pulling focus (you know those shots where you have the subject that is out of focus and then it becomes clear - the Gaussian blur effect) and getting amazing bokeh shots, which involves manual focus. You could get bokeh with AF, but with MF... the control is with you and you get the bokeh shot with the first shot (instead of trying multiple AF releases - trial and error). So the first thing you do is put your lens in MF mode (look for switch on the lens itself), point the camera towards your subject and before you press record, zoom into the area you want in focus (2 buttons on top right with 2 blue magnifying glass symbols + and - signs below the buttons), and use the focus ring to focus. Once its properly focused, press the record button.
