The actor, 38, was seen carrying the 5-year-old into the Wiltern Theatre ahead of Jessie‘s performance.
News of their relationship broke in mid-October, when an insider told PEOPLE, “It’s very new.”
Since then the Magic Mike star also supported Jessie, 30, at her Houston concert on Sunday.
“Channing is her biggest fan,” a source says. “He flies all over the U.S. to attend her concerts.”
Tatum and Everly’s mom Jenna Dewan announced their separation in April after nine years of marriage and filed for divorce on Oct. 26 in Los Angeles, citing irreconcilable differences. They’ve both asked for joint legal and physical custody, and Dewan has requested child and spousal support.
The exes remain amicable, though, and took Everly out trick-or-treating together for Halloween on Wednesday. Everly dressed as Teen Titans superhero Starfire, Dewan, 37, was Cleopatra and Tatum went as Genie from Disney’s Aladdin. The Step Up costars even documented the evening on Instagram and snapped a smiley selfie.
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A source revealed that the former World of Dance host and the theater actor, 43, have been “dating for months” and “have a lot in common.”
“Jenna is having a lot of fun with Steve,” the insider added. “They’ve been dating for months out of the spotlight and it’s becoming more serious.”