Mom and 5 month old Costumes?

My birthday is on Halloween and my baby girl will be 6 months on the 23.  Im excited because this is her first Halloween and I want us to both dress up as something. Like I was thinking she can be Dorthy and I can be the Wicked Witch or something like that. You know? Something that goes together. I was wondering if anybody can give me some good ideas for costumes. Would be appreciated😊