Usually when you need to reference something inside your theme you can use this WordPress function
Which works fine if you’re using a standard WordPress theme. However, if you are using a child theme or a framework like Genesis then the above will actually tell you where the parent theme is located, not the location of your child theme.
Try this instead.
$sample_image = dirname(get_bloginfo('stylesheet_url')) . "/images/people-example.jpg";
In this example, I want to access an image “people-example.jpg” that’s stored inside the child theme in a directory called “images”.