ROCKER LISA MARIE DISPLAYS HER TWIN BABY GIRLS.

Photo by John Russo

Elvis Presley's only daughter, Lisa Marie, is now a doting mom to 3-month-old girls Finley and Harper – and she is showing off her tiny additions in the new issue of PEOPLE.

"I really wanted these babies," says Presley, 40, who tried for two years to get pregnant before conceiving the twins.

"My blood was too thick and would clot, which caused several miscarriages," she tells PEOPLE. "The moment I took blood thinners, I got pregnant."

Presley and her guitarist husband Michael Lockwood, 47, also share their L.A. home with Presley's children from a previous marriage: daughter Riley, 19, and son Benjamin, 16.

Source: PEOPLE