You got such great advice here.  And I had to laugh as it sounds like some of us were raised by the same mommas'!  My house, my rules, no ifs ands or buts, was the first thing that came to mind.    
I liked Maximo's suggestion, have a room you can key lock, and put the pups in, they will be safe.  This is a great idea particularly if your pups are not crate trained, and not just for visiting badly behaved grandchildren either.  When you have workmen through the home, doggies are safe!  When you have guests that are very scared of dogs, doggies are safe.    
Your step grand daughters behaviour was appalling, and her kids are obviously out of control.  No doubt about it.    
But for me, there are a couple of things at play here in my mind.  As the host I was taught that guests to my home were treated very well.  I have some friends (not many), and one neice who are afaird of my big breed.  I know this, and yet I want her and my friends to be able to visit my home in a way that is comfortable for them.  I truly don't want to miss out on their company.   
So for me I have always crate trained my dogs, and while they would love to be part of the company (always), I will crate the dogs when these people who are special to me are invited over.  In the scheme of life, my boys who are crated for 4-5 hours it is not too much of a hardship for them.     
With everyone else, I have developed some short rules, and for first time visitors I pre-explain to them, how to meet and greet my dogs, what to do and how to behave.  I in other words stage manage the situation.  ANd that includes for my wee Yorkie.     
Set up a set of short rules/guidelines, and ask your visitors to follow them.  After all it is for every-ones safe enjoyment of the visit.    
And I do agree with every-one who posted that this is their (the dogs' home), but it is MY HOME first, and everyone in it comes under my rules.  
Most especially my dogs are expected to obey my rules.    
Maybe that sounds harsh to some.  But an unruly dog just like an unruly child needs rules and discipline.  And for me that means sometimes you can be part of the company, and sometimes not.    
I do so hope your Christmas goes better than Thanksgiving did.     
				__________________  Razzle and Dara. Our clan.  RIP Karma Dec 24th 2004-July 14 2013 RIP Zoey Jun9 th 2008-May 12 2012. RIP Magic,Mar 26 2006July 1st 2018     |