Teigen was quick to respond, writing, "four weeks sober," adding a prayer hands and love-heart emojis.
Teigen briefly addressed her sobriety on Christmas Day, saying in a post, "Trying to figure out if my love of face crystals is a phase of sobriety or a lifestyle."
She has previously talked about her alcohol consumption, telling Cosmopolitanin 2017 she was "point blank, just drinking too much".
The model's decision to be sober comes three months after her heartbreaking miscarriage where she lost her third child around halfway through her pregnancy.
Teigen took to social media last week to make a very personal admission about the possibility of falling pregnant.
In a raw and emotional post, the star said that she would never be pregnant again, after experiencing the tragic loss.
Posting a side-on photo of herself, Teigen explained how she still has a baby bump, which serves as a painful reminder.
"This is me and my body, just yesterday. Even though I'm no longer pregnant, every glance in the mirror reminds me of what could have been," she said.
"And I have no idea why I still have this bump, honestly. It's frustrating. But I'm proud of where this entire journey took my body and mind in other ways.
"I love being pregnant, so, so much, and I'm sad I never will be again. But I am lucky to have two amazing little ones who are transforming into big little people more and more every single day. Anyhoo. Love u guys. Xx."
Teigen and husband John Legend are the parents to daughter Luna, 4, and son Miles, 2.
They lost their third child, who they started calling Jack, when Teigen was 20 weeks pregnant in September.
Since then, the star has begun "intense grief counselling" to help deal with her loss.
A source told Us Weekly earlier in December: "It is going to be a long and hard journey, Chrissy is doing her best to work on herself and stay positive."
"I'm not tweeting much because I'm honestly in a bit of a grief depression hole," she tweeted in November.
"But do not worry as I have so much help around me to get better and I'll be fixed soon."
