Kourtney Kardashian receives baby well-wishes from sisters Kim, Khloe and Kendall

Kourtney Kardashian and Scott Disick welcomed their second child Sunday (July 8) - a little girl named Penelope Scotland Disick. Naturally, her sisters were quick to post their congratulations online.

Kim Kardashian writes, "Welcome to the world, Penelope Scotland Disick! Kourtney gave birth to a beautiful baby daughter on Sunday and the whole family is so thrilled to finally meet her! She is absolutely perfect! I am so excited to be an aunt again and can't wait to spoil little Penelope. I know Mason is going to be the best big brother in the whole world. Congratulations Kourtney and Scott. Xo."

Khloe Kardashian Odom tweets, "Such an amazing day!!!!!"

Kendall Jenner writes, "great day! #babytime #PenelopeScotland" ‪

Penelope Disick joins big brother Mason, 2 1/2 years old.