The Carpenter Prince by S.A. Sommers

Once upon a time in a land far, far away… Well, maybe not that far away. Okay, it’s Virginia.
Two kids met on a playground and had a great day together. For the heck of it, as the sun set over the jungle gym, they got pretend-married.
Except it wasn’t pretend.
It was all very, very legal in that country far away. And now, the new king of Iodannes, Valon, has come calling for his bride.
The only problem is, his blushing bride’s name is now Jason.