Well they don't get much cuter than this pair of rascals! You know the old saying; " Never work with children or animals", so the first thing to consider is whether you will be bothered by being upstaged? If not, read on.... what else might happen? Well kids are unpredictable; you can dress them up in cute outfits and rehearse with them what they will be doing, and they might still decide differently on the day. They may get shy, feel overwhelmed or just for their own reasons have a change of heart. One of my own daughters ( aged 5) was very put out to see when she arrived at her Aunt's wedding as a flower girl, that the groom was in full army uniform with a ceremonial sword. " Oh no, I'm not doing this, I don't like soldiers", she announced loudly.... (The two cuties pictured above were simply angelic on the day!)
If the little ones are in the wedding party or guests, they are likely to get bored. Most ceremonies last about 30 minutes, and mine usually involve telling the love story of the couple. Most guests love that part, but funnily enough it doesn't play well with the under 12s... So top tip: have someone (other than immediate family) on standby to take small children out if they get restless, this is particularly important if you are videoing the ceremony, you don't want a crying baby on the tape. Older kids can be kept entertained with colouring books/snacks etc.
On the plus side, children can add a wonderful, joyful perspective to a wedding. Little flower girls tossing rose petals/small boys carrying up the wedding rings can be a big wow factor at the start of the wedding. Even if they do sit down half way up the aisle, or stop to have a chat with granny on the way, it's a lovely way to signal that this is a relaxed, child-friendly wedding. So if you don't mind the unexpected, I'd say go for it! And remember, if it's your own little one, there is always an option to include a " baby welcoming" or " baby naming" piece to the ceremony - you're all dressed up, the family is present and there is food coming , go for it!