Kristen Bell gives birth to a second daughter

LOS ANGELES, Dec. 20 (UPI) -- Kristen Bell and her husband Dax Shepard announced via Twitter they have welcomed a second daughter into the world.

The couple, who married in October 2013 after six years of dating, named their newborn Delta Bell Shepard. They also are the parents of Lincoln Bell Shepard, who was born in March 2013.

"The estrogen has now hit critical mass! Good luck, @daxshepard1. And welcome to the world DELTA BELL SHEPARD :)," Bell joked.

"She doesn't look like either @IMKristenBell or me, but we're gonna keep her anyway," Shepard tweeted.

Bell is known for her work in the Frozen and Veronica Mars movies, as well as on TV's House of Lies.

Shepard is a cast member of the long-running series Parenthood.

The estrogen has now hit critical mass! Good luck, @daxshepard1. And welcome to the world DELTA BELL SHEPARD :) pic.twitter.com/72AFmnjmoC

— Kristen Bell (@IMKristenBell) December 20, 2014

Delta Bell Shepard is here. She doesn't look like either @IMKristenBell or me, but we're gonna keep her anyway. #christmascameearly

— dax shepard (@daxshepard1) December 20, 2014