Hi Tina,
Welcome back to the Disney Parks Moms Panel and thank you for asking us another question!
I’m not familiar with the specifics of the Bo Peep costume that is available at Target, but I’ll assume that the shepherd’s staff that comes with it is hollow or made of very light plastic. Keeping that in mind, I’ve taken a look at the
Special Event Costume Guidelines that apply to
Mickey's Not-So-Scary Halloween Party, and I think that the staff that goes with your daughter’s Bo Peep costume should fall into the category of “acceptable accessories” for the event.
Of course, please note that the
Cast Members at Security may judge that it too closely resembles an actual weapon or that it may accidentally strike another Guest, so your daughter might need to leave her staff behind when you arrive for the Party. That being said, based on my experience, the costume guidelines are usually interpreted pretty loosely for child costumes, and usually only disallow accessories that truly look like weapons from entering
Magic Kingdom Park during the Event.
Please don’t hesitate to come back and see us if you have any other questions!
Have a Magical Day,
Lynne