LO at a wedding

Mimi
I'm planning to bring my LO to a friend's wedding in March. She'll be shy of 4 months old. We have our friend's consent to bring her. Is it a good idea to bring her?  Would my baby be able to sit in a high chair at that age? What do we need to bring other than a diaper bag. My worry is will we have to hold her the entire time? Anyone have experience with this or heard stories of how to handle this situation?