Having your adult child living under your roof can have its challenges (and its rewards), but things can get more intense over the holidays, when family tensions tend to build.

If you have an adult child living in your home (or are expecting one to stay with you over the holidays while visiting) the key thing you can do is sit down and talk about what the living situation will be, before your grown son or daughter comes in the door — or soon afterwards.

You need to make sure you all agree about what’s acceptable, and a written agreement can be an great way to make sure you cover all the issues and everyone is on the same page.

After all, the relationship between parents and their children is always a parent-kid relationship, with all that that entails, no matter how old the child is or how long they’ve been on their own.

Here are some issues that should be part of the conversation, to ensure peace and goodwill in your home this Christmas:

– Household rules, including swearing, late nights, and noise: Especially if your kids are coming home from college and is used to college-style language, music, and hours. Talk about what you’re comfortable with, and what you’re not.

– Who covers additional expenses: If your adult kid is just home for the holidays, this probably isn’t an issue. But if they’re home for a month or more, who’s going to pay for the extra groceries they consume and the electricity they use? Remember that food bills especially can pile up over the holidays.

– Which chores your grown kids will be responsible for: A Christmas break with no help from your adult kids could leave you fuming. Make sure you agree on what’s expected beforehand so your kid doesn’t feel imposed upon, and you don’t feel resentful.

For more tips on keeping the peace — at any time of year — check our my 115-page eBook, contract template, and household expense calculator, all for only USD $27.97 now just $19.97 for the holidays for a limited time!