Kyle gave a smile and then looked at Stephan, telling him, "I am fine with it. As long as you are okay, Lianne and Joseph are welcomed at any time. It would give Junior some company as well."
Kyle knew his spouse well.
You have to respect his position as the head of the household and be gentle. Stepping back would make him much more receptive to whatever was being asked.
Kyle found that men generally had these huge egos. They couldn't 'lose face' in the sense that they need to be the one that makes the decision. His spouse wasn't so bad as he did discuss things, but at the end of the day, if he made a decision, that's it.
No budging.
Kyle got his way most of the time by using the soft approach and it looks like Lianne learned it well. You do not go head-on against Stephan, but cajole him or let him think (and feel) that he was the one making the decision.