Took possession, sellers haven't moved

[Cathy Malmrose]

My son bought his first home, $400k, and took possession, but the Sellers asked for another week to move. For some reason the realtor didn't suggest a lease back to cover this time period so now my son "owns" a house but has not taken possession and was not given the keys. He is a very generous person by nature so I wasn't surprised to hear he is allowing them time to move because he is single, doesn't need to move right away and is busy with work anyway. What is the shortest way to explain to him (without stressing him) that tells him the realtor dropped the ball? Big time. So far I have: 

1. This is a holdover seller situation and the realtor put him in a situation of liability.  

2. Who has insurance on the home while they are moving out?   

3. Who covers any damages that occur to the home during move out? 

I don't know what else to point out. All I know is that the Mama Bear in me is furious. This is in Utah, a state where I bought and sold only two SFRs, but both times were problematic. (The last transaction ended with the disbursement check amount being different from what it said on my closing docs -- I was the seller, I signed first. I didn't notice until I had driven away and when I went back to the title company, everyone else had left the office and the clueless secretary said "Oh, they changed what they wanted to pay because the buyers said they didn't want to pay that much." They changed the dollar amounts on the document AFTER I had signed.)