Duck Dynasty's John Luke Robertson pops the question to Mary Kate McEacharn – and she says yes!

The eldest son of Willie and Korie Robertson, John Luke, is set to wed his sweetheart Mary Kate McEacharn.

John Luke popped the question on his 19th birthday, Us Weekly reports, and he couldn't be happier, telling the magazine that he is "so excited to marry my best friend".

"I know my parents married young as well, and they have always been examples of what 'could be' to me," he said.

"Fast-forward 22 years and they are more in love than ever, and I hope Mary Kate and I are the same way in the years to come. God has truly blessed us."

His sister Rebecca Robertson was among those expressing their delight over the news.

She wrote to Mary Kate on Twitter: "She said YES @marykatemce so excited to be your sister."

The tweet included a sweet picture of the three of them:

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She said YES

John Luke has also been busy on Twitter sharing inspirational quotes and some of them reveal his approach to relationships.

"A real man never stops showing a woman how much she means to him, even after he's got her," he shared on September 19.

He followed a couple of days later with some wise words about fidelity: "Stay faithful or stay single."

Although she didn't mention anything about his engagement, John Luke's sister and Dancing with the Stars contestant Sadie Robertson shared a cute message and photo on her Instagram.

"I love you so much & I'm blessed with a spiritual leader as a brother. You are such a blessing to me in so many ways," she wrote.

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hApPy BiRthDay to the John Lukey :-) I love you so much & I'm blessed with a spiritual leader as a brother. You are such a blessing to me in so many way. And to the handsome man on the left of me thanks for sticking with me for the past 9 months. You rock. Love these 2 amazing guys ♥️

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