Mystics star and WNBA champion Elena Delle Donne has spoken often about her relationship with her older sister, Lizzie, who was born blind and deaf, and with autism and cerebral palsy. The pain of being separated from her sibling who communicates only through touch and scent was one of the main reasons Delle Donne transferred from U-Conn. to Delaware, a 15-minute drive from her childhood home, as a freshman in college, and why she forced a trade from Chicago to D.C. in 2017.

“Saying goodbye to Lizzie wasn’t okay,” Delle Donne told The Post three months after the blockbuster deal made the Mystics instant title contenders. “I wasn’t able to handle it.”

The Delle Donne sisters were featured on an episode of HBO’s “Real Sports with Bryant Gumbel” earlier this year, during which Delle Donne said that she and her wife, Amanda Clifton, will become Lizzie’s full-time caretakers when her parents are no longer able. The sisters are also the focus of a Nike commercial that will air during Thursday’s Cowboys-Bills game on CBS.

“My sister is the inspiration for all of my choices,” Delle Donne says in the one-minute spot, which will also be featured during Friday’s Pelicans-Thunder game on NBA TV, and during additional NBA games throughout December. “She gives me strength. Everyone thinks I carry her. But she’s the one carrying me.”

In August, Delle Donne debuted a laces-free Nike shoe that was designed with people like Lizzie — and athletes with disabilities — in mind. It features a magnetized heel that folds down, making it easy to put on and take off without using one’s hands.

En route to leading the Mystics to their first WNBA title, Delle Donne averaged 19.5 points and 8.3 rebounds and captured her second MVP award. She also became the first player in WNBA history to shoot at least 50 percent from the field, 40 percent from three-point range and 90 percent from the free throw line for a season. The NBA’s Larry Bird, Steve Nash, Mark Price, Reggie Miller, Dirk Nowitzki, Kevin Durant, Stephen Curry and Malcolm Brogdon are the only other members of the 50-40-90 club.

None of Delle Donne’s accolades matter to Lizzie.

“Lizzie doesn’t know that I play basketball,” Delle Donne told “Real Sports.” “She doesn’t know that I’m 6-5. She just knows that I am one of her people, and a really important person in her life. And that’s all I want to be.”

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