It is exciting to see the photographer working on the portraits, especially if you are familiar with the style of that photographer.
What it gives you in practical sense it’s some action. The difference between your camera and a still camera is that you can shoot the girls approaching and leaving the spot. They look different; some feel awkward. Their looks, their smiles, put them all on video. Use a variety of shots. Alternate wide shot of the entire scene with extreme close up of the bride or the flower girl. Or start on the close up of a bouquet and zoom out to the group shot.
Do groups in action, people setting for a shot. Use close up to capture the reaction of people interacting with each other.
