Julie and Todd Chrisley Wish Son Grayson Happy 16th Birthday as They Face First Day of Court

Julie and Todd Chrisley are celebrating their youngest son's milestone birthday as the first day of their federal trial begins.

The Chrisley Knows Best stars — who are facing charges of tax evasion and bank fraud, among others — each penned a sweet note to son Grayson, who turned 16 Monday, with Todd writing, "@graysonchrisley this day 16 years ago was one of the greatest days of our lives, I thank God each day all day long for blessing us with you and I love you more than words could ever express, with all my heart Thank you for just being you."

Todd, 53, also posted a handful of photos along with his birthday message, with the first photo being a picture of the father-son duo from a recent nature outing, while the second took a trip down memory lane with a throwback snap of the pair. The third photo shows Todd and Grayson from the back, walking down a hallway with their arms around each other.

Grayson's mom, Julie, 49, also got in on the birthday action, posting a sweet message of her own in honor of the teen's special day.

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"Happy Birthday @graysonchrisley I can't believe my baby is 16 today! I am so proud of the young man that you are," she wrote. "I love you with all my heart and thank Hod [sic] everyday that he chose me to be your mom! #happybirthday #sweet16."

Todd and Julie are currently facing a federal trial in Atlanta after being indicted by a federal grand jury in August 2019 on 12 counts of bank and wire fraud, tax evasion, and conspiracy, which they have denied.

In a lengthy Instagram post defending himself and his wife, the patriarch pointed blame at a former employee. While he said that he wouldn't "go into details," he claimed that the case "involved all kinds of really bad stuff like creating phony documents, forging our signatures, and threatening other employees with violence if they said anything."

RELATED VIDEO: Todd and Julie Chrisley Plead Not Guilty to Tax Evasion: 'The Good Lord Will Hold Our Hand'

Todd added, "We know we've done nothing wrong. … I'm telling you all this now because we have nothing to hide and have done nothing to be ashamed of."

The two were cleared of their state tax evasion charge in Georgia in early October 2019, but continue to face federal charges for allegedly evading federal taxes in the same years.

U.S. District Judge Eleanor Ross said jury selection was set to take place Monday with opening statements expected on Tuesday, per The Tennessean.