I can't even believe I am asking this, but I've been anxious about doing the right thing lately and have been reading your page a lot. When my husband was a child, his parents held a joke wedding ceremony between him and another little girl. They were no more than 5 or 6 years old. I only know about this because I saw pictures. I don't think anyone considered this a real wedding ceremony, and I don't know what kind of "vows" were exchanged. Due to the age of the children, and the fact that this was considered a joke, can I be assured that this "marriage" was not valid in the eyes of God?
The children were not of an age to be able to enter into a covenant. They are not old enough to know what they are committing to, so cannot enter a vow. This is one reason minors in most countries cannot enter into a contract.
A real wedding ceremony would have violated the laws of the country because they were below the legal age, and Christians are to obey those laws when they are not in conflict with God's laws (Romans 13:1-2). Therefore another aspect of covenants, a witnessed record of the event, could not have taken place.
However you look at it, no marriage took place.