"Well, I guess dry January is done," Reese quipped in the caption, tagging her daughter in the post which saw Reese in a gorgeous green floral wrap dress from her brand Draper James, and Ava rocking a tan suede skirt with a black shirt sleeve roll neck.
WATCH: Reese Witherspoon's throwback marks big milestone
Fans and friends were quick to comment with Julianna Marguiles joking: "Oh thank God!"
"Cheers to the weekend!" added Reese's company Hello Sunshine as others branded the pair "gorgeous" and many couldn't help but reference how similar the mother-daughter duo look.
Reese welcomed 22-year-old Ava during her marriage to Ryan Phillippe, and the pair are also parents to son Deacon who recently turned 18.
The Legally Blonde star made sure Deacon had a day to remember for the special celebration, and the teenager was joined by both his parents for the occasion.
Reese and Ava celebrated with champagne
Proud dad Ryan Phillippe took to Instagram to share a lovely picture of himself, Deacon and ex-wife Reese smiling at the table in a restaurant in front of a birthday cake, alongside a heartfelt message.
The actor wrote: "Happy 18th birthday to our gorgeous, smart, talented, and caring son. You are a true light in this world and are so loved by all who know you." He then added: "We are lucky to be your mom and dad. Love you, pup..(I’d say we did pretty good @reesewitherspoon."
Reese was quick to reply to the comment, writing: "So proud of our boy. I mean our ADULT son!" alongside a love heart emoji. Deacon replied too, adding: "Thanks dad!! I love you."
Proud dad Ryan took to Instagram
Reese is also mom to Tennessee, nine, whom she welcomed with husband Jim Toth.
Ava regularly speaks with fans in her comments section, but recently sent a powerful message to fans, days after she shared that she did not consider gender when dating.
"I can and will block profiles commenting bigoted/hateful messages under my posts," she wrote on instagram on Thursday.
"My Instagram profile is not a place for cruelty/hate speech and I intend to do what I can to keep it that way." She signed off with "peace and love".
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