Heidi Montag Wants To Reproduce. Quick, Somebody Do Something

And baby makes three?

Stephanie Pratt says her sister-in-law Heidi, 22, is eager to start having kids.

See Heidi and Spencer’s wedding album.

“Heidi is the one with the baby fever; Spencer is not,” Stephanie, 23, tells MTV News. The drama will be caught on cameras for the sixth season of The Hills, premiering Sept. 29.

“Here’s the deal: Basically, Heidi got married … She’s like, ‘Thank you, God, for my marriage. What do I do?’” Stephanie says. “I really feel like she went to a bookstore and saw Newlyweds: The Wife’s Edition, and so now she’s like, ‘I still want to get a house with a white picket fence…and then probably a dog, and then we’ll move on to kids. And I want to take cooking lessons.’”

Look back at Nick and Jessica’s happier days from The Newlyweds.

Stephanie says Heidi is not ready for kids yet.

“I’m like, ‘You don’t have to do that,’” she said. “I keep telling her, ‘You don’t have to get a dog [either].’

Check out photos of Hills stars at the beach.

She doesn’t even think Heidi is ready for a dog.

“A dog is a kid,” Stephanie says. “They’re just too busy.”