As her December due date approaches, Kim Kardashian is beginning to wonder how North West will react to welcoming a new baby into their family.

"Not going to lie, I'm a little nervous about bringing baby No. 2 into the mix," the 35-year-old reality star wrote in a candid new blog post on her website on Friday. "I'm nervous about how North will react, but I know she'll be such a good big sister and I can't wait to have this addition to our family. I know it won't be easy-North even has a hard time adjusting when I hold other babies!"

As for how she and hubby Kanye West are prepping North to get used to the idea of a little brother, "We read books with her about getting a baby brother and a new sibling all the time!" she wrote. "We always say goodnight to baby brother."

North also looks to cousin and BFF Penelope, Kourtney Kardashian's daughter, for guidance. "Right now anything her cousin Penelope does, she does," Kim revealed. "So it's really helpful that P has a little baby brother!"

In the meantime, Kim wants to spend as much time as possible with her adorable little girl. "I don't have that many more nights with just me and her before the baby comes and changes her world completely," she explained. "I'm really trying to spend most of my time at home so we have this special bonding time."

West is particularly excited about having a son. "You're such a good daddy to North," Kim captioned a precious photo of him and North when they first revealed the gender. "You will be the best daddy to our new son too!" Their son could have an extra-special birthday, too, as it has been rumored that the doctors plan on delivering him on Christmas day, as HNGN previously reported. There's a good chance she could have him before that, though, as North was born a month early.