Mouse event for mouse stand on an object

Hi,
I’d like to animate a button when I put the mouse over it. What’s the problem?
I use mouse_over or roll_over events, ok.
But what if I hide the button when I click it and then I show it again later without moving the mouse? The mouse stays over the button, but the button does not animate, as there is no out/over event: I have to move the mouse out and over again to see the animation.

How can I detect the mouse standing on a button without the out/over event?
Thanks!