images that appear when sharing site on social media

Hi, I was wondering if you know of a way to change what image is pulled from the website when sharing on social networks?

For example… http://www.suemcdonnell.com.au/ when I share it on linkedin, it comes up with the blog image which is not really want to appear, I would rather some of the brand images to appear. do you know how this can be controlled?

Thanks,

Robyn