Kim and Kroy had a son in May and now that she's four months along in her pregnancy, the boys will be very close in age, which is what the couple wanted.
"They're so excited because Kim already had two girls and now that she's having a second son, the family will be balanced out with two of each," a close friend told Star.
"Kim was trying to hide it, but she's showing a little already."
Kim, 33, has two daughters from a previous marriage, Brielle, 15, and Ariana, 9.
For more details check out the new issue of Star magazine on newsstands Thursday.
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