Saint West tested positive for Covid-19.
The five-year-old son of Kim Kardashian West and Kanye West seemingly contracted the virus sometime in 2020, his mom revealed in a preview of the next episode of 'Keeping Up with the Kardashians' which airs on May 27.
Kim's daughter North, seven, also felt poorly at the same time.
The 40-year-old reality star - who also has Chicago, three and Psalm, two, with her estranged rapper husband - says on the phone in the promo clip: “Sainty just tested positive for Covid. And North is saying she’s feeling sick.
“I’m trying not to freak anyone out, but I’m just really worried.”
It's not known exactly when the youngster tested positive.
Saint's dad claimed he tested positive for coronavirus last February.
The 43-year-old star said at the time of his symptoms: "Chills, shaking in the bed, taking hot showers, looking at videos telling me what I'm supposed to do to get over it."
And Khloe Kardashian was also struck down with the virus and spent 16 days in isolation.
The 36-year-old Good American co-founder documented her battle with the virus and admitted creating herself an imaginary friend helped her through.
Khloe - who has two-year-old daughter True Thompson with Tristan Thompson - cobbled together a new pal, Quarantina, out of glasses and a neck pillow.
She said: "I decided to have an imaginary friend, Quarantina.
"I'm just getting lonely and bored and I need someone to keep me company.
"Quarantina is literally saving me right now.
"'Cause, I need something to do all day long."
Tristan joked she had turned into Tom Hanks' character Chuck Noland from 2000 film 'Cast Away', after he made a "friend" out of a volleyball and smeared blood when he was stranded on an uninhabited island.
He said: "It's like Tom Hanks. 'Cast Away'."
But the pro basketball player did offer Khloe some emotional support.
He told her: "If you ever need a friend to talk to, I'll stand outside your window downstairs.
"Like, back in the day, when guys would throw rocks at girls' windows to talk to them. We could always do that, take it back to the early '90s."
After her 14th day of quarantine, Khloe admitted Covid-19 was the "worst sickness" she had suffered, because she had been "shaking for no reason", struggling to breathe, and "coughing uncontrollably".
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