If the kid has observed half an hour of a fight at home, then he has probably absorbed more than what he would usually absorb in a week’s time. The fights are usually not in the service of divine matters, are they? You fight for the sake of money, or you fight because you are jealous, or you fight because of unmet desires, sexual needs.
So, while it is important to think of the kid, it’s a little more important to take care of oneself as a parent.