Kim Kardashian is jealous of her pregnant older sis, Kourtney.
"I want a baby!" Kim, 28, posted on her Web site Thursday.
"OK, so maybe not right now, but I can't wait to be an aunt," she added.
She says her maternal instincts were sparked after shopping with Kourtney, 30, last week in Miami.
"It's really fun, but we have to stay neutral when you're shopping for a baby and you don't know what the sex of the baby is. I found that really hard..." Kim wrote. "I just wanted to to shop for pink or blue, haha! I want Kourt and Scott to find out already!!"
Kourtney told Us Weekly last week that she doesn't know if she'll find out the sex of her baby, due on Christmas.
"I'll probably find out, but I haven't decided for sure," she said.
She also revealed that she's not sure what she and Disick will call their child.
"I don't have any names that I'm crazy about yet," she said. "I just got a name book that Scott's parents sent me."