He's ready for his close-up! Well, not exactly, but proud mommy Julia Roberts did flash a picture of her adorable 5-month-old baby boy, Henry, on screen yesterday when she stopped by for a chat with Oprah. "I have to say, little Henry's the sweetest child known to mankind," bragged mom. "I think I can say that objectively." Oprah was smitten, too: "Henry is the cutest munchkin," she declared. "He's just the cutest baby boy." Let's hope Julia's fraternal twins, Hazel and Phinnaeus, don't get too jealous!