twenty eleven – post page #primary background not repeating.

Looks like you have quite a few mark-up errors that are likely causing that:

https://validator.w3.org/check?uri=http%3A%2F%2Fsweetpapertrail.com%2Ffacebook-fan-freebies%2F&charset=%28detect+automatically%29&doctype=Inline&group=0

Especially the ones having to do with missing, extra, unclosed or open tags.

https://codex.www.ads-software.com/Validating_a_Website

Also, you really should not be modifying theme files — as your changes will be overwritten when WP is updated. Instead, use a Child Theme: https://codex.www.ads-software.com/Child_Themes

I do have a child theme but for some reason its not reading changes on it.

The site you linked to is not a child theme – did you activate it once you created it?

yes It’s activated. I’m not sure why it was not showing up.

Question if its markup errors, why is it not causing this to happen in the home page and only in the post pages?

I have been looking over the errors. And most of them are part of the theme and nothing that I have created. Could it be something else? When I use the firebug and remove this :

#page {
background: none repeat scroll 0 0 transparent;

it fixes it…. but then my header does not show a transparent background, is there a way to call just the header out for a transparent background?

OK so I checked all the errors and nothing.

Any thoughts on the css fix? I have tried everything.

The problem on that page is that the sidebar is longer than the center section. If you want a transparent header, the best way to do that is to use a transparent image as the background in that element (not the whole page). You’ll need to make the image using an image program such as photoshop.

So it appears to be that when there is enough content the background extends further down to fit… is there a way to set a minimum before it starts to expand?

Interesting solution. How can I do double backgrounds? so I could tile the one I have and then add the header as a background? How would I remove the header but leave enough space for the background to show thru?

These are pretty specialized CSS questions, so you might get better help on a CSS forum such as https://csscreator.com

Nope actually it was a pretty easy fix, after many hours of looking at the wrong thing… I figured it out!

All I needed to do was add a min-height to the #primary.

There was no need to change absolutely anything else, just add
#primary{
min-height: 1900px;
}