If you are attending a wedding with your children you will most likely want them to wear something special for the day. Many people hire outfits for wedding but with children, it may be hard to do this as you may find that they spill things down them or get dirty from rolling around.
Ideally you want to find an outfit that they will be able to wear again as it can be a bit of a waste of money buying one outfit that will not be suitable for anything else.
If you are buying for a boy then you could buy a suit that has a waist coat and trousers as they could then wear the trousers separately as well.
When choosing an outfit, think about colours as white may look very nice but will often not stay white for long and therefore will become ruined often after only one wear.