Barrymore on Baby No. 2: It's Really for Olive

Drew Barrymore, 38, is opening up to People about her second pregnancy, speaking out for the first time about her big baby news that broke Monday.

Drew says that the main reason her and husband Will Kopelman are "overjoyed" about baby number two being on the way, is the fact that their daughter Olive, 1, will now have a sibling.

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"Will is just thrilled — we both are — [because] we just wanted so badly for Olive to have a sibling," she says. "In some ways, it's really for her. So congratulations, Olive!"

And clearly, Drew couldn't be feeling any better about a second child being on the way.

"It always feels so surreal, it's incredible," she shares. "[I'm feeling] incredible, that 'Here we go again' feeling. And blessed. Blessed! ... I'm feeling very, very happy. Happy and healthy — mentally and physically."

As for why she's going public about this pregnancy, she says it's to avoid the paparazzi frenzy that surrounded her when she was pregnant with Olive.

"Last time I never commented on it and people just stalked me the entire time," she tells the magazine. "So yes, it's happening, it's true. I tried to keep it a secret for as long as possible."

On a more lighthearted note, the Never Been Kissed actress admits to already having pregnancy cravings -- particularly one type of cuisine that she currently "can't get enough of."

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"Oh my God, I’m eating everything! I can't get enough of Chinese food," she reveals. "It's all I want to eat!"