'Duck Dynasty's' John Luke Robertson and fiancée: God guides our relationship

While most 19-year-olds are focusing on college life, "Duck Dynasty's" John Luke Robertson and his fiancée Mary Kate McEacharn are busy planning their wedding.

The eldest son of Willie and Korie Robertson proposed to McEacharn after receiving permission from both of their parents on his 19th birthday, Oct. 11.

"I never had a boyfriend before and I had just been waiting and thought God would send someone to me," McEacharn told FOX411. "I was just very particular whenever it came to who I would date and I had to get to know him first and see if he was up to my standards."

It took weeks of long rides to and from McEacharn's church to give chemistry tutoring for Robertson to finally win over his sweetheart.

"It took some work and trying," Robertson said while his fiancée laughed in agreement.

When the young couple finally started dating in March 2014, their faith played a critical role in their relationship.

"We said in the beginning when we started dating that if our relationship is not centered on God and if we're not encouraging one another to stay faithful and to just love people then we have no relationship at all," Robertson told FOX411. "When I was growing up [my parents] taught me to set my own rules and guidelines, to stay pure."

One factor that the young couple had to deal with was the Robertson's fame. The success of "Duck Dynasty" meant all eyes were on the teenagers once McEacharn said yes.

"It's definitely been interesting," McEacharn said of adjusting to dating the reality star. "I guess through our dating life, I was seeing how it was for him and seeing what all of that was about. I didn't realize how much things would change though when we did get engaged. It has been very interesting, but good, all that's happening."

For Robertson, who recently released a faith-based fiction series called "Be Your Own Duck Commander," his family's fame means the opportunity to share his message of faith with his fans, he said.

"What I always remember about God is that one, He's real and everything points to that," he said of advice he gives fans. "If He is real, and He's the God of the Bible, then He loves you and if you stick with Him, He's going to get you through and three, to find other people who think the same the way because life is all about relationships."

While the Robertson clan and McEacharn's families are thrilled for the young couple, many have criticized them for getting married at such a young age.

"As far as negative people go, we decided a long time ago we weren't going to listen to them," Robertson said of his critics. "As far as being married goes, everyone has said something about us getting married too young and I think pretty much all of them are unmarried."

"The people that matter to us, support us," McEacharn said.

Although the couple have yet to set a date, Robertson would get married "right away" while McEacharn intends to plan a summer wedding. One surprise the reality star has for his bride?

"Yeah, I'm working on [growing a beard] but Mary Kate doesn't know it yet," he revealed to his fiancée who said, "We'll see."

Faith & Fame is a regular column exploring how a strong belief system helps some performers navigate the pitfalls of the entertainment industry.

Follow Sasha Bogursky on Twitter @SashaFB.

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