"For some reason, North hates when I feed the baby, and she lays on my lap so Saint can't be right in front of me to eat, LOL!" the 35-year-old reality star writes on her site (which is produced by mom.me parent company Whalerock Industries).
While sibling rivalry might be getting its usual start, Kardashian West has found a way to ease her young daughter into the process.
"I've started to include her: Sometimes I will pump and have her feed him the bottle," Kardashian West, who is married to Kanye West, reveals. "That totally worked! She loved helping me, as opposed to my attention being off of her, and now she is my helper."
The mom of two also weighs in on public breastfeeding, which has become a hot-button topic among moms and others with a strong opinion on the subject.
"Now that I'm a mom," Kardashian West writes, "I say whatever makes you comfortable goes."
Still, she says that she wouldn't "breastfeed in a restaurant with a bunch of people I didn't know staring at me," and even admits that before motherhood she tweeted her shock at the practice when she saw it herself.
That said, now that she's a mom, she writes, "I'm not that shocked, especially if you have a few kids and can't leave to breastfeed one kid in the bathroom while leaving the others at the table."
In fact, she says now she would breastfeed in front of girlfriends, because "it's such a natural experience and I'm not shy about that."
One celebrity mom who hasn't been shy about public breastfeeding is Alyssa Milano, who has received flack for posting breastfeeding photos on social media. Kardashian West, however, shares her support for moms like her.
"I know so many people get backlash for posting breastfeeding pics," she writes, "but I don't mind them!"