I created a skin using the instructions within this website and uploaded it. I added the skin. However, I keep getting the following error message with a blank page below it.

Fatal error: Call to undefined function: posts_nav_link() in /home/content/t/w/i/twimom/html/confessions/blogs/skins/twimom/index.main.php on line 284

If I delete the line that it refers to, I get the skin, but the area that should contain the blog is blank.

http://www.confessionsofatwilightmom.com/confessions/blogs/blog1.php

Why is this occuring?

I followed the instructions regarding the memory, as well as creating the php.ini file for hosting with Go Daddy and none of these have corrected the error.