The 'Dun-Dun, Baby Girl Is One' theme was a no-brainer for Dara and her husband, who are longtime fans of the series A Law & Order-themed birthday party ... a lot this year and so this was just ...

now 1 year old, dances when she hears the various Law & Order theme songs Dara tells PEOPLE how she picked the perfect details to make a Law & Order theme fit her daughter's birthday party ...