Nicole Richie is set to give Access Hollywood's Billy Bush (in photo) an exclusive about her embattled family relationships.

The interview, which airs tonight and tomorrow, will see the mom-to-be opening up about her biological parents, from whom she is estranged, and about her adoptive father, Lionel Richie.

POPSUGAR reports that Nicole was given up by her parents at age three, and now feels compelled to reconcile with them. 

"When I found out that I was pregnant, there was just something inside of me that felt a responsibility to mend any issues that I've had with my parents…You just want to heal any wounds before I become a mother myself," she states in the interview.

She also tells viewers that Lionel was at first shocked by the pregnancy, but soon "came around."

Lionel, she says, has "all these names he's ready for the baby to call him" instead of 'Grandpa.'

"He doesn't like 'grandpa.'"

Nic says that she and fiance won't tie the knot this year, and that she has decided not to find out the sex of her baby (although Lionel says HE knows!).