Jason and Shady have been married for five years but say their marriage is on the verge of falling apart. Living under one roof with all seven of their children, they say they are at odds over how best to parent the kids, and the constant fighting is taking a toll on their relationship.

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In the video above, Dr. Phil offers advice on how they can get their marriage back on track and how they can bring harmony to their home.

“You’ve got to understand one thing for absolute, drop-dead certainty: You cannot discipline her children. You cannot discipline his children,” he tells the couple. “If you were going to be in a father role for these children, you would have needed to be in there before 5 years of age. You weren’t, so you can’t do that. You can support her in disciplining her children, and you can support him disciplining his.”

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He suggests they negotiate rules for the children that they both agree on, so all the children are held to the same standards. “Children have to know that they are all loved the same and that they are all treated the same,” Dr. Phil says.

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To rebuild Shady and Jason’s relationship, Dr. Phil suggests the couple go to pre-marital counseling. “You need to sit down and say, ‘Let’s design a family that we actually begin to create some traditions. We actually begin to do some things where the children want to be part of this.”

This episode of Dr. Phil airs Wednesday. Watch more here.