Ashlee Simpson has released the first picture of her baby daughter.

The 'Pieces of Me' singer and her husband Evan Ross welcomed Jagger Snow into the world on July 31 and she has taken to Instagram to unveil a portrait of herself, the 'Hunger Games' star and their new addition, all dressed in white.

Alongside the picture, in which Evan is holding baby Jagger while Ashlee looks on, the 30-year-old singer wrote: ''Jagger Snow Ross !! We love her so much!!! She is beyond everything!!! I have the best baby daddy @realevanross In the world. Love you (sic)''

It was recently revealed Ashlee - who also has six-year-old son Bronx with ex-husband Peter Wentz - and Evan ''couldn't be happier'' with their new family unit and were spending as much time together as possible.

A source said: ''Ashlee and Evan couldn't be happier.

''Right up until Ashlee gave birth Evan was playing shows quite frequently, working hard on his album but since Jagger was born he's put his music on hold and has been spending most of his time with Ashlee and the newborn. Only family and a few friends have seen Jagger but they say she's adorable.''

And Ashlee's father Joe has admitted he is smitten with the ''precious'' little girl, whilst he also revealed he and his ex-wife Tina were both present in the delivery room.

He said previously: ''Jagger is precious. She's quiet and sweet and she's such a happy baby. The apple of her papa's eye. She's beautiful. She looks like her mommy and daddy.

''I got to take a picture of my little granddaughter the day she was born! In the room with the baby, it was great to watch them have that moment. And, you know, grandparents, we were standing back. What a beautiful thing to watch.''