No, it shouldn't be normal. It is unhealthy & it is not a good example for you. A home should be filled with nothing else but love.
Not really , though if you've been here on EP for any length of time , you'll see it happens more than you'd think , maybe it was very serious and things needed to come out , just be there for them and give hugs ... that's all I got since we have nothing else to work with from your question ... They'll hash it out