Kylie Jenner is going to become a mom at 18!

An insider reveals to Life & Style that the teen is pregnant with her first baby — and 26-year-old boyfriend Tyga is the father!

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“She’s gained a little weight and she says she’s been having the weirdest cravings for Roscoe’s House of Chicken and Waffles and Krispy Kreme Doughnuts,” the insider adds.

The little bundle of joy will join Tyga's three-year-old son, King Cairo, from his previous relationship with Rob Kardashian's current girlfriend, Blac Chyna.

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"All [Kylie] can talk about is baby names, whether she’ll have a boy or a girl, how she’s going to decorate the nursery and the child’s wardrobe.”

But, not everyone's excited over the news. The source tells Life & Style that Kylie's older sisters, Kim, Khloé and Kourtney Kardashian all think it's a huge mistake. And while momager Kris Jenner "wasn't surprised" by the announcement, she's "not exactly thrilled."

For more on Kylie's pregnancy, pick up the latest issue of Life & Style, on newsstands now!