As upsetting as it can be for a parent, conflict between siblings is pretty common.
As kids grow they compete for everything from toys to attention, and different stages of development bring evolving needs which can spawn jealousy, bickering and squabbles.
The Brothers Harbaugh are getting ready for one of the biggest sibling rivalries of all-time in Super Bowl XLVII when John's Baltimore Ravens take on Jim's San Francisco 49ers, but this isn't Peter and Bobby Brady splitting the room down the middle with some masking tape.
This is a good-natured clash between two brothers who have grown into a pair of the best football coaches in the world.
Jackie and Jack Harbaugh, the parents of the Harbaugh boys, and Joani Creen, their younger sister and wife of Indiana basketball coach Tom Creen, talked with the media on Thursday in an effort to highlight the interesting position the family is in.
Jack, a former head coach himself on the college level at Western Michigan and Western Kentucky, gets a lot of credit for molding the two minds that became the first brothers in history to meet as head coaches on the NFL level but he never pushed either in that direction.
"I think they both decided to get into coaching on their own," Jack Harbaugh said. "They loved sports, had a passion for sports. They enjoyed being around the game. Then came a time to make a decision in what their life���s work would be, and they decided on coaching."
The first matchup between Jack's boys, on Thanksgiving in 2011, was won by John's Ravens, 16-6. The sequel will take place in front of 100 million or so of the Harbaughs' closest friends.
"I think I will start with the idea after the AFC Championship game. I felt that was a joyful moment for them, for our whole family, our extended family and for my father who is 97 years old," Jackie said. "(It was a) great feeling of joy. I know one is going to win and one is going to lose, but I would really like to end in a tie."
"Can the NFL do that?" she laughed.
A tie isn't an option and that has many probing the inner workings of the family's minds, trying to hit on something.
A lot of people are rooting for John, the perceived "underdog" who rose up through the NFL ranks the hard way. The Ravens head coach wasn't a star quarterback at a football factory like Michigan, wasn't a first round pick by a marquee franchise like the Chicago Bears, didn't spend 14 years in the NFL as a player, and wasn't the flavor of the month as a coaching candidate after a stellar stay at Stanford -- that's Jim's resume, a big man on campus-type background.
John spent his college years as a defensive back at Miami-Ohio, and was perhaps best known as the roommate of Brian Pillman, who went on to become a huge wrestling star with both Ted Turner's World Championship Wrestling franchise and Vice McMahon's World Wrestling Entertainment empire.
The older Harbaugh brother didn't play a down in the NFL and spent 13 years toiling the college ranks as an assistant at places like Western Michigan, Pitt, Morehead State, Cincinnati and Indiana before Andy Reid gave him a shot as the Philadelphia Eagles special teams coach.
John tutored the Birds special teamers for nine years before getting promoted to defensive backs coach and most were stunned when the Ravens took a flyer on him and made him their head coach in 2008.
Hindsight says Baltimore was right. Under John, the Ravens have recorded at least 10 wins in four of five regular seasons, and own the NFL's second-most wins (62, including playoffs) since his arrival in the Charm City. One more victory in the Super Bowl and Baltimore would match New England, who has amassed 63 wins since '08.
Joani was quick to defend Jim, who is 27-8-1 through two years as the Niners coach with two NFC Championship Games and a Super Bowl appearance, however.
"I would have to respectfully disagree with that in a sense," their sister said when asked if John had a tougher road. "Jim has worked incredibly hard at every turn. Whether it was fighting to be in the NFL -- his seven years with the Bears and three spectacular years with the Colts -- a lot of hard work came into that every day.
"Even with the Oakland Raiders, he put in more hours ... we hear about his deprived sleep and sleeping on the couch there, and he has really done an incredible job. For after only being a head coach in the NFL for two years, because of all of the hard work he has put in up until now "
Mom then explained each's journey.
"John made his choice to become a football coach, he started as a graduate assistant, and he worked his way up through the ranks at different colleges along the way," Jackie Harbaugh said. "I think what has happened for both of them, all of the lessons they have learned along the way through their hard work, also observing how other coaches handled their team .. they had put so much time and energy into this."
So where do the family loyalties lie?
'John from Baltimore' jumped on the line and asked the toughest question of the day.
"Is it true that both of you like Jim better than John?"
John Harbaugh couldn't fool his family, at least his sister anyway.
"Hey, John, how are you?: Joani said, quickly recognizing her brother's voice.
"Mom was ready to come right through this phone (and fight the questioner). I am so happy Joani recognized your voice," Jack said.
The real answer, of course, was simple.
"We are neutral in the Super Bowl, and we are just excited that they have brought their teams to the pinnacle of sports," Jackie said. "The Super Bowl is the ultimate accomplishment for them and for their teams and for all of the extended football family and all of the teams who have participated in this great game. We are excited for that type of thing."
And in the end, no matter the score, the Harbaugh family is already the big winner.
"I think the greatest joy I got in my life -- after seeing all of the ups and downs, and the ins and outs, and all of the different things involved in the coaching profession -- is that is something they would decide [to do]," Jack Harbaugh said. "It was something they wanted to do."