You can also insert a picture box into a text box, which would allow it to stay at a particular point in the text. So, for example, if you added an extra paragraph at the start, the picture would shift with the text.
To do this, you need a text box and a picture box. Use the 'Item' tool (the arrows) to select the picture box, and copy it (or cut it). Now use the 'Content' tool (the hand) and click somewhere within the text box. Now paste. There are a few options in the measurements pallette regarding alignment, but that's the basic principle.