“Today” Co-Host Sheinelle Jones' 'Family Health Matter' Is 'Serious,' Source Says: 'A Sensitive Time' (Exclusive)

"Sheinelle appreciates the support she’s received from fans and viewers in her absence," an insider says

Sheinelle Jones revealed on Wednesday, Jan. 15 that she is taking an extended break from the Today show to deal with a family health matter. And while she did not disclose the nature of the issue, a source close to Jones tells PEOPLE the situation is "serious."

According to the insider, the health matter does not concern Jones herself or the three children she shares with husband, Uche Ojeh: 14-year-old Kayin and 12-year-old twins, Clara and Uche.

"Sheinelle appreciates the support she’s received from fans and viewers in her absence," the source says. "She’s especially grateful for her tight-knit Today show family and co-hosts, for all their love during a sensitive time."

Related: Sheinelle Jones Reveals 'Family Health Matter' Is Behind Her Lengthy Absence from the Today Show: 'I'll See You Soon'

Related: Craig Melvin Emotionally Reflects on Landing Today's Top Anchor Seat: 'This Is a Gift and It's Not Lost on Me' (Exclusive)

Jones, 46, first joined Today in 2014 and has been a constant across all of Today's programming. In addition to co-hosting 3rd Hour of Today alongside Al Roker, Craig Melvin and Dylan Dreyer, Jones also regularly fills in as co-anchor for Today, and guest co-hosts Today with Hoda & Jenna (now dubbed Today with Jenna & Friends).

The mother of three has been absent from the program since Dec. 18, sparking questions from viewers.

In a post on her Instagram on Wednesday, Jones thanked the fans for their concern. "I sincerely appreciate all of you who have reached out while I’ve been absent from the show. I want to share with you that I’m taking time to deal with a family health matter," she wrote.

"It’s not lost on me how lucky I am to have not on the the support of my Today show family, but to also have all of you," she added. "Your kindness means so much to me. I’ll see you soon"

The post was signed, "Love, Sheinelle."

Today viewers know Jones regularly shares stories about her family on the program and on social media.

This Spring, she'll release her first book Through Mom’s Eyes, which is inspired by the recurring Today segment she leads interviewing celebrities’ mothers about raising successful kids.

Out April 15, the book will feature Jones' own journey through modern parenting as well as valuable lessons about life, love, and parenthood from the moms of Lady Gaga, Kevin Durant, Matthew McConaughey, Venus Williams and Serena Williams, Lin-Manuel Miranda, Steph Curry, Padma Lakshmi, Tyra Banks, Donnie Wahlberg and Mark Wahlberg, Rob “Gronk” Gronkowski, Jessica Simpson and Ashlee Simpson, Shaquille O’Neal, Brandon Maxwell, the Jonas Brothers and Thomas Rhett.

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Writing the book, Jones told PEOPLE in August, helped her learn things about her own mom.

"Even while I was writing this, there were times that were really tough and I would be writing a chapter with Lucille O'Neal, Shaq's mom, and she talked about alcoholism, and I'm going through my own thing and I'm like, ‘You know what? She was able to push through that and motherhood didn't stop,’” Jones said.

“And so I think you'll find a thread at the end of this book. I hope it's inspiring,” she added. “I hope people laugh a little bit. They may shed a tear or two, but ultimately it's my love letter to moms.”

The Today show airs weekdays (beginning at 7 a.m. ET) on NBC.