The Ghost Clause by Howard Norman

They fell in love with the house and purchased it.  The woman selling it was a widow.  In that state old houses had a special clause in the contract that if a ghost bothered them, the seller would have to buy it back.  They just thought it was funny.  After all, the owner knew of no ghosts.  So they married and moved in.

Houghton Mifflin Harcourt and Edelweiss allowed me to read this book for review (thank you).  It will be published July 2nd.

What no one knows is that Simon, the dead husband, still lives there in ghost form.He watches the young couple and their cat, reads books in their library, and sets their burglar alarm off.  He figures he won't be there for forever but he's enjoying this time he's been granted.

The burglar alarm company is losing patience with them, they've got normal marital adjustments to make, and the previous owner visits quite often.  Her husband enjoys those visits.

The kids eventually realize Simon is there but they don't fear him.  

This is really a tale of two marriages.  It's almost mundane but the ghost adds flavor.  The ending was surprising but appropriate.  It's a nice, easy read.