For the Samuelson sisters, UConn’s Katie Lou and Stanford’s Karlie, the Final Four is a family affair

Katie Lou Samuelson felt a little nauseous. Pretty much on par with how she typically felt in these situations.

She was sitting in the corner of a small locker room at Webster Bank Arena, site of the NCAA women’s basketball Bridgeport (Conn.) Regional, with teammates and assistant coaches huddled around her.

The Huskies were dressed for practice leading up to the regional championship the following day, but for the time being they were focused on a tablet showing another game, between Stanford and Notre Dame, being played in Lexington, Ky., more than 700 miles away.

Stanford was attempting to rally from a 16-point deficit and Samuelson had a rooting interest: Her older sister Karlie, a senior at Stanford, was trying to extend her college career and help push the Cardinal to the Final Four.

“I feel very sick to my stomach watching their game,” Katie Lou said as media obligations pulled her away from the game. “But I get that nervous for every game she plays.”

A short time later, a Huskies assistant coach shouted an update: “Hey! Up one, Lou!”

Katie Lou, in the middle of an interview, smiled and gave a thumbs up.

In the end, Karlie scored 15 points as Stanford pulled out a 76-75 win to advance to a national semifinal against South Carolina on Friday in Dallas.

The next day, Connecticut, with sophomore Katie Lou scoring eight points, routed Oregon, 90-52, to advance to a national semifinal against Mississippi State.

All of which means that Jon Samuelson, their father, enjoyed nothing but winning basketball as he bounced back and forth between airports and games.

“We are super excited,” he said in a telephone interview this week from the Hartford airport, where he waited to board a flight home to Southern California after Connecticut’s regional win. “Stanford was kind of unexpected. We knew they had a shot, but it was such an exciting win. And for Karlie, her senior year, to get to the Final Four is incredible. And then to have two of them there, it’s unbelievable.”

While Jon traveled between the regionals, his wife Karen served as traveling secretary from the family’s Huntington Beach home. The whole family, including oldest daughter Bonnie, will make the trip to Dallas.

Katie Lou, 6 feet 3, and Karlie, at 6 feet, have never played against each other in college. In high school, they were teammates one season at Huntington Beach Edison High, then again in 2012 at Santa Ana Mater Dei, helping the Monarchs to a 30-2 record and state Division I championship.

Karlie then followed Bonnie’s footsteps and accepted a scholarship to Stanford. But two years later, Katie Lou broke tradition and decided to attend UConn, about 2,900 miles away.

“Of all the girls, Katie Lou was kind of the one who did her own thing with recruiting,” Jon said. “She made her own decisions about it. When she went there to visit she just decided that was the place for her.”

Said Katie Lou: “I’ve really loved my time here so far and I’ve definitely felt every single day that I made the right choice and that I wouldn’t be as happy anywhere else.”

With the Huskies, Katie Lou has never lost a college game. UConn has a 111-game winning streak that dates to 2014.

Connecticut Coach Geno Auriemma often points out Katie Lou’s weaknesses in attempts to motivate her. He’s also made a habit of mentioning Karlie, who averages 12.8 points, 3.5 rebounds and 2.7 assists for the Cardinal.

“A week doesn’t go by when I don’t say, ‘Man, we got the wrong Samuelson,’” Auriemma said with a chuckle. “[Stanford] got the one that plays really hard, is really emotional, dives on loose balls and plays good defense. We got the wrong one. I must say that once a week just to get Lou a little pissy. It works all the time.”

Katie Lou joined the Huskies 37 wins into their streak, shooting her way into the starting lineup midway into her freshman season. This season she is averaging 20.3 points, shooting 48.6% from the field and has made 116 three-point shots, five shy of the single-season school record, while earning first-team All-America recognition.

She said Karlie, who always challenged her in backyard games, continued to play a role in her success. The sisters try to watch all of each other’s games.

“She kind of will tell me exactly what she thinks of the game and what she thinks I need to do better,” Katie Lou said. “She’s been really helpful for me this year and I probably should give her a lot of credit for some of the things I’ve been able to do this year.”

If Stanford upsets South Carolina and Connecticut defeats Mississippi State, the sisters will play each other for a national championship on Sunday.

“I’d be really nervous,” Jon said. “It would be really difficult, especially if they got matched up against each other. I just wouldn’t know what to think.”

UConn would be playing for a fifth consecutive national title and the second of Katie Lou’s career. For Karlie, it would be her final game Stanford.

So how will their parents feel? “It would be a … I mean …” Jon stammered a bit searching for an answer.

Finally he said, “I guess it’s a good problem to have.”

lindsey.thiry@latimes.com

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