Sadie Robertson Is “So Excited” About Brother John Luke’s Engagement to Her “Best Friend,” “Can’t Wait” to Be a Bridesmaid

Sadie Robertson and John Luke Robertson
Sadie Robertson tells Us Weekly she's "so excited" about her brother John Luke's engagement to her "best friend" Mary Kate McEacharn, and "can't wait" to be a bridesmaid  Courtesy Curtis Hilbun

That's just ducky! Sadie Robertson couldn't be more excited about her brother John Luke Robertson's recent engagement to Mary Kate McEacharn. Us Weekly caught up with the Duck Dynasty star at the Monday, Oct. 13, taping of Dancing With the Stars, where she gushed about how thrilled she is to welcome McEacharn into the family.

"I knew like two weeks before," Sadie, 17, said of her brother's plans to propose. "It was really hard for me to keep it from her since we are best friends. Mark [Ballas] almost ruined it!"

Indeed, Ballas  Sadie's pro partner on season 19 of DWTS  told Us he nearly let the secret slip. "All her friends came into our rehearsal and they were hanging out, and John Luke came in [with Mary Kate] and I was like, 'Hey buddy! I heard…' I was literally about to say, 'I heard you're going to have a big day soon,' and as I was saying it, someone tapped me on the shoulder and I turned around and forgot my thought," he confessed. "Can you imagine?"

Fortunately for John Luke, 19, McEacharn didn't suspect a thing. "I honestly had no idea," the bride-to-be, 18, previously told Us of the Oct. 11 proposal, which went down before her beau's birthday party at the family farm. "I think I went into a [state] of shock. I was just like, 'Is this for real?'" 

It is  and Sadie, for one, "can't wait" for the "I dos," which she said will happen in June. In fact, she's already thinking of ways to help with the planning, not just as a sister but as a member of their wedding party. "Of course [I'll be a bridesmaid]!" she gushed to Us at DWTS. "It's my brother and my best friend! I have to!"

She added: "[Mary Kate's] been my best friend for a long time, so it's going to be so awesome to have her as part of the family  she's going to be a Robertson!"

For more on John Luke and Mary Kate's engagement, plus photos from the celebration afterward, pick up the new issue of Us Weekly.

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