Charlotte Seibert already has an outfit picked out for her first viewing of the University of Michigan-Ohio State football game.

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Born into a family of longtime Buckeye fans, the 7-month-old will don scarlet-and-gray pants at her grandparents' annual viewing party for the big rivalry game.

But the words on her onesie — "My first Michigan shirt" — may draw a few gasps from the crowd.

"We have big Ohio State fans in my family, so they may be quite aghast," says her mom, Lauren, with a laugh. "It will have some shock value."

She and her husband, Jack, have a softer spot for the Wolverines after Charlotte received open-heart surgery at University of Michigan C.S. Mott Children's Hospital in October.

"After all they've done for her, she's allowed to be a Michigan fan," Lauren says.

Heading north for critical care

In fall 2017, the couple were eagerly anticipating the 20-week ultrasound of the unborn child who would make their 2-year-old son, Graham, a big brother.

That's when they learned shocking news: Their baby girl had a life-threatening heart defect.

"That was a really tough day for all of us," Lauren says. "It was devastating, given that we weren't anticipating anything to be wrong — and then having to think about what would be next."

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More scans and heart echocardiograms indicated a complex set of congenital heart conditions.

Charlotte had a hole in her heart known as a ventricular septal defect and transposition of the great arteries, meaning the two main arteries leaving the heart were reversed. The condition prevents blood from circulating through the body, leaving it without enough of the oxygen-rich blood it needs to function.

After researching their options, the family from Northwood, Ohio, decided to travel an hour north to Mott, which has an international referral center for children with complex congenital heart disease.

"Our cardiologist said the best people to do this are at Michigan," Lauren says. "We would have traveled anywhere to make sure she had the best chance, but Michigan was the best place."

Michigan team works magic

The family also opted to deliver Charlotte at Mott so she would have immediate access to the hospital's care team.

Another benefit: Lauren could remain nearby, as U-M's birthing center at Von Voigtlander Women's Hospital is just a couple of floors away in the same building.

SEE ALSO: Buckeye Fan Thankful for Treatment in 'Enemy Territory' After Cardiac Arrest

Charlotte was born in April and was doing so well that the team waited until she was bigger to perform the surgery.

A week before her scheduled procedure in October, however, a cardiac MRI showed that Charlotte's heart condition was more complex than doctors initially thought. She would probably not be able to have a repair to a normal, four-chamber heart.

The alternative, which seemed inevitable, would be a series of two operations.

But instead, during the 3½-hour procedure led by Mott pediatric heart surgeon Richard Ohye, M.D., the congenital heart team performed a double outlet right ventricle repair, an arterial switch operation and a resection of blockage of the artery from the heart to the lungs to fix the defect.

The procedure eliminated the need for future surgeries.

"It had been such a roller coaster, and we were worried that she'd need more surgeries down the road and never have a normal heart," Lauren says. "But when we got paged in the middle of the surgery and heard that it was going even better than expected, that was such a relief.

"Dr. Ohye was able to work a lot of magic that day."

Limitless potential and 'dual loyalties'

Today, the brown-eyed baby is offering big smiles and starting to babble. And her parents are relieved they won't have to keep their healthy girl from participating in any childhood activities.

"I was worried that she might not have the chance to play sports or have to be treated differently from her brother," Lauren says. "But nothing will limit her. She can be a normal kid, just with a small scar on her chest."

Even though Lauren and her husband have spent most of their lives cheering for the Buckeyes, Lauren says she's OK with her daughter having "dual loyalties."

As one of Charlotte's favorite onesies says, she'll "always be a Buckeye fan" but "my heart belongs to Michigan."