The actress and her British beau couldn't wait to announce their arrival, taking to Instagram to share a sweet snap of Dave with their newborn.
The couple even treated fans to the name of their little girl, revealing a rather unique choice!
Liv, 39, posted the adorable snap with the caption: '💗Hello!!!!!💗 our beautiful baby girl is here !!!!💗 Lula Rose Gardner 💗 we are sooooo happy 💗 heart exploding with love !!!!!💗 @davidgardner'
David, a sports agent who counts David Beckham as his best friend, can be seen holding his baby daughter in the black and white picture. He also shared the same photo to his Instagram account, and couldn't wait to express his joy at becoming a dad for the second time.
'Our gorgeous baby girl has arrived "Lula Rose Gardner" unbelievably beautiful, healthy and thank goodness she looks like her Momma !!!!
'Truly blessed [heart emoji] Daddies girl....Now the real work starts training her big brothers to all become Ninja's, Martial Arts Experts & 24-7 Body Guards !!! @misslivalittle'
Liv and Dave welcomed their first child - a baby boy named Sailor Gene Gardner - in February last year. The Lord Of The Rings actress has an 11-year-old son, Milo, from her previous marriage to Royston Langdon, and Dave also has an eight-year-old son - Grey - from his previous marriage to Davinia Taylor.
The actress first announced she was expecting the couple's second baby with a sweet Instagram snap, which showed her with a hand on her growing bump. She captioned the pic: 'Oh my goodness it seems the stork is visiting us again !!!! I am growing another little Tyler Gardner in my belly. Our family is growing!!! So grateful. @davidgardner I love you (sic).'
Liv, whose father is rock legend Steven Tyler, went public with her relationship with David in 2014.
It was revealed last September that the happy couple are engaged, after David reportedly popped the question over the previous Christmas.