Problem with menu button

I’m building a small site and one of the menu buttons have three child pages. (e.g. Photos > childhood, wedding, kids) On rollover this button the child pages drop down. Besides, it also has onclick function as usual. As Photos has no content I don’t want it to have this function. I’d like a visitor can only rollover Photos and choose one of this dropped down childhood, wedding, kids pages.

What is the solution of this problem?
Thanks in advance.