18-Year-Old Quadruplets Loved Growing Up Together, but They’re ‘Excited’ to Go to Separate Colleges (Exclusive)

“We're just like, ‘Yeah, it's pretty normal,’ because that's the only thing we're used to," Gavin Michaels, 18, tells PEOPLE about growing up as a quadruplet

NEED TO KNOW

• Quadruplet siblings Gavin, Reese, Lauren and Maggie Michaels just graduated high school together last month — but after a lifetime of togetherness, the next chapter will be a big change for the whole family
• The four are all heading off to different colleges in the fall, a reality that’s just now beginning to hit them
• “I was actually really struggling with this two days ago,” Lauren, 18, tells PEOPLE

Husband and wife Jon and Tiffany Michaels felt a wave of emotions as they watched their 18-year-old quads  — son Gavin and daughters Reese, Lauren and Maggie — graduate from Normal Community High School last month.

“We're thankful for who they are and happy for them,” Jon, 49, tells PEOPLE. “But at the same time, it's a little sad for us because it's like, ‘Oh, we're getting close to them departing.’ ”

The Champaign-Urbana family says that having quads in the family has proved to be the ultimate fun fact.

“You get a lot of shock at first and then they want to go straight to ‘What was it like raising them when they were babies?’ “ says Jon. “A lot of people want to know the hows.”

After years of fertility struggles, Jon, who works at an insurance company, and Tiffany, who designs school uniforms, welcomed the four siblings through in vitro fertilization on Feb. 19, 2008.

“I was just so thrilled to be pregnant,” says Tiffany, 46. “I was so thankful and blessed that we were going to be able to have children.”

The Michaels siblings say growing up as quads gives them a lot to be grateful for.

"We have a really great bond, so we can tell each other anything," says Lauren. "Not a lot of siblings have that and it really helps because we're literally the same age."

“We get the question asked a lot: ‘What does it feel like having three other siblings?’ " adds Gavin. “We're just like, ‘Yeah, it's pretty normal,’ because that's the only thing we're used to.”

When it came to celebrating their birthdays as children, each of the Michaels siblings would pick their own cake and get their own “Happy Birthday" serenade.

“Looking at other people who don't share a birthday, it's definitely probably nice to get your own,” muses Maggie. “But honestly…I wouldn't trade it for the world.”

Seeing all her four kids graduate last month was an emotional experience for Tiffany and Jon, especially when they paused to think about the fact that in just a few short months, they'll be empty nesters.

Going to college will also come as a big shock for the quads themselves as each is set to attend separate schools in different states.

It'll be the University of Cincinnati for Gavin, while Maggie will attend the University of Northern Iowa. Meanwhile, Lauren is attending Illinois State University and Reese will be off to the University of Missouri. 

The quads, whose story was previously covered by local affiliate WEEK, have mixed feelings about being away from each other, but they’re also eager to embark on the next chapter of their lives, too.

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“I was actually really struggling with this two days ago,” Lauren tells PEOPLE, “because it just hit me. So I was in a really hard spot because we're just so close as a family."

“Obviously I'll miss my siblings, but I think I'm excited just to go see what it's like without my siblings for a certain amount of time and just grow as a person,” adds Reese.

But no matter what, their mom says "they're always welcome home" — and, she says, "when they're home, we'll pick up right where we left off and just enjoy the time we do have together."