Robyn Lively on 'doing the mom thing' with sister Blake Lively: 'I genuinely feel like her children are mine'

'Tis the season of sisterly love.

Actress Robyn Lively gushed over her close relationship with younger sister Blake Lively in an interview with Fox News Digital.

Despite their 15-year age gap, Robyn, 50, says she and her younger sister, Blake, 34, are only getting closer as the years go by. The Teen Witch star credits motherhood for unlocking a new level of bonding for the pair.

"There's a significant age gap which feels almost nonexistent because she's now a mom," said Robyn, who shares three children with actor husband Bart Johnson. Blake, meanwhile, has three daughters with Ryan Reynolds.

Between acting, motherhood and marriage, the two are able to connect on multiple levels, regardless of age.

"We have so many similarities," Robyn added. "Our relationship is on a deeper level. We used to help each other with our projects and lines, things like that. Now we're doing the mom thing together.

Robyn noted that the sisters are also close to one another's kids.

"I genuinely feel like her children are mine as if I gave birth to them, and vice versa," she said. "We’re like, ‘your children are mine too.’ Our relationship has only gotten richer and fuller."

Her husband told Fox that the sisters are "like the same person."

"They've got the same energy and the same sense of humor," said High School Musical star Johnson. "They're also so connected and love each other so much. It's really gone a long way since Robyn was on Savannah and Blake would come to hang out on set as a little girl."

"Our kids are the center of our entire universe," he added. "[Robyn and Blake] share the love and the passion for motherhood. They're best friends. It's such a charming friendship. It's a beautiful thing."

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