Actionscript 3 :: Way To Tell Canvas To Dispatch Event Only If Not Over Child?

I got a square component inside a canvas which when clicked shows a glow effect-indicating selection-while clicking somewhere else this effect is removed-indicating deselection.The problem is that the canvas always dispatches the "deselect" event, even if the mouse if over the square.I worked around this by defining a circumstantial function which removes the child's width,height from the parent's "clickable" area.Is there a better way to tell the canvas to dispatch his event only if not over the child ?