Jay-Z writes song for new daughter

Beyoncé and Jay-z have welcomed their first child - a baby girl named Blue Ivy.

Singer Rihanna was one of the first celebrities to welcome Blue Ivy into the world, tweeting: "Welcome to the world princess Carter! Love Aunty Rih".

Blue Ivy was born on Saturday by Caesarean section at Lennox Hill hospital, New York. 

The couple released a statement saying:

"Hello Hello Baby Blue! We are happy to announce the arrival of our beautiful daughter, Blue Ivy Carter, born on Saturday, January 7, 2012.

"Her birth was emotional and extremely peaceful, we are in heaven. She was delivered naturally at a healthy 7 lbs and it was the best experience of both of our lives.

"We are thankful to everyone for all your prayers, well wishes, love and support - Beyoncé & JAY-Z"

Beyoncé is said to have check in under the fake name 'Ingrid Jackson' and to have spent over $1.3million taking over an entire floor and bullet-proofing the maternity wing!

Singer Nicki Minaj is rumoured to be lined up as Blue Ivy's godmother.

Jay-Z has ALREADY released a track featuring Blue Ivy's sounds and murmurs to celebrate her birth.