I will explain how to change their icon in blogger.
following way;
1. go into your blogger account
2. then to the layout
3. then edit the HTML
4. search code <head>
5. after met <head> code, then copy the code below and place in the code <head>
<link href='http://picture.jpg/gif' rel='shortcut icon'/>
6. replace the red text with your picture icon with jpg or gif format
7. when it's finished, save their HTML