Site logo disappearing, being replaced by images on page

by the way I am using the latest version of wordpress twenty eleven, woocommerce and have a childs theme installed

this is a feature of Twenty Eleven, to use the featured images of single post or static page in the header, if these images exceed a minimum dimension.

to change this feature, you will need to edit header.php in your child theme and remove/change some of the code.

change this section:

<?php
					/*
					 * The header image.
					 * Check if this is a post or page, if it has a thumbnail, and if it's a big one
					 */
					if ( is_singular() && has_post_thumbnail( $post->ID ) &&
							( /* $src, $width, $height */ $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), array( $header_image_width, $header_image_width ) ) ) &&
							$image[1] >= $header_image_width ) :
						// Houston, we have a new header image!
						echo get_the_post_thumbnail( $post->ID, 'post-thumbnail' );
					else :
						// Compatibility with versions of WordPress prior to 3.4.
						if ( function_exists( 'get_custom_header' ) ) {
							$header_image_width  = get_custom_header()->width;
							$header_image_height = get_custom_header()->height;
						} else {
							$header_image_width  = HEADER_IMAGE_WIDTH;
							$header_image_height = HEADER_IMAGE_HEIGHT;
						}
						?>
					<img src="<?php header_image(); ?>" width="<?php echo $header_image_width; ?>" height="<?php echo $header_image_height; ?>" alt="" />
				<?php endif; // end check for featured image or standard header ?>

to:

<?php
						// Compatibility with versions of WordPress prior to 3.4.
						if ( function_exists( 'get_custom_header' ) ) {
							$header_image_width  = get_custom_header()->width;
							$header_image_height = get_custom_header()->height;
						} else {
							$header_image_width  = HEADER_IMAGE_WIDTH;
							$header_image_height = HEADER_IMAGE_HEIGHT;
						}
						?>
					<img src="<?php header_image(); ?>" width="<?php echo $header_image_width; ?>" height="<?php echo $header_image_height; ?>" alt="" />

(not tested)

Thanks so much, works like a charm.

I appreciate it alchymyth!