However, little is known about Jenner’s first and eldest child, Cassandra Marino.

Cassandra, who is wed to Michael Marino, was born on June 10, 1980.

“We have a very complex relationship,” Marino told host Diane Sawyer.

Cassandra Marino and Caitlyn Jenner

“[She’s] disappeared out of our lives, especially out of my life.

I’m looking forward to this next chapter.”

And I apologized to my kids for that."

The Jenners with kids in 1991 including Cassandra Marino

Since then, it’s been a different kind of relationship for Jenner and Marino.

“I am pleased with how beautiful and comfortable she seems every time I see her.

The Jenner family in 2016