Lucie Arnaz said her brother “just likes to stay a bit ‘undercover'” in an Instagram post on Saturday, Aug. 3.

Lucille Ball’s son Desi Arnaz Jr. is making a rare appearance on social media.

On Saturday, Aug. 3, Lucie Arnaz, 73, posed with her brother, 71, in two photos shared among a carousel of images on Instagram as the pair attended a family dinner while in Las Vegas for STLV: The 58-Year Mission.

One snap showed Lucie resting her head lovingly on Desi Jr.’s shoulder while posing with her hands wrapped around his arm. Another shot showed them both looking at the camera.

In the caption, Lucie — who is the child of the late I Love Lucy stars Ball and Desi Arnaz, as is her brother — thanked her husband Laurence Luckinbill’s son Nick for treating them to a “grand meal at Wally’s,” she wrote in the caption.

“With our special guest, my recalcitrant brother, Desi Arnaz, Jr.!!! Desi is alive and well, my friends- just likes to stay a bit ‘undercover,’ ” Lucie added.

“We are here for the weekend as Larry is being tributed during the 35th Anniversary of Star Trek V celebration at The Treksperts Convention here. He played Spock’s brother, Sybok in that film – and with his autobiography just released, is a very special guest here,” the caption included, referencing Laurence’s role in 1989’s Star Trek V: The Final Frontier.

Lucie added of her husband, who released his book Affective Memories: How Chance and the Theater Saved My Life in April, “He’ll be taking photos, selling and signing books and speaking on two panels.”

Other photos showed her posing with friends including Vegas entertainer Clint Holmes and his wife Kelly, as well as Maximillian Von Anhalt and Sunny Sessa.

“I snuck away to Caesar’s and Joe’s Seafood to join the indomitable Sunny Sessa, her dear Max and our pals, Clint and Kelly Holmes for more stimulating conversation and just a few naughty sweets!! What smart, interesting, funny, involved and talented and lovable friends and family have I,” Lucie concluded, adding multiple hashtags to mark the evening.

Desi Jr. has kept himself out of the spotlight in recent years after the death of his wife, Amy Arnaz, to cancer on Jan. 23, 2015. She was 63.

Meanwhile, Lucie and Desi Jr.’s parents divorced in 1960, and though it was difficult in the beginning, the two remained close.