Kanye West has written a lullaby for Jay Z and Beyonce's daughter Blue Ivy.

The 'Bound 2' hitmaker presented the track to the tiny tot - who celebrated her second birthday on January 7 - as he wanted to do ''something personal'' for his rap star pal's child.

A source told the Daily Star newspaper: ''Kanye wanted to do something personal for his best friend's baby.

''So he decided he would write and record a lullaby especially for her. It won't be released, it's just for Blue. He hopes it'll help send her off to sleep at night.''

Kanye has seven-month-old baby North, who is nicknamed Nori - with reality star fiance Kim Kardashian - and hopes she'll become friends with Blue.

The lullaby is about how doting dads Kanye - who dropped out of Chicago State University much to the initial displeasure of his mother Donda West when he was 20 - and Jay Z - who grew up in Brooklyn, New York City, in the tough Marcy Houses housing project - will make sure their daughters don't have to face the same struggles they did.

The source added: ''It's really catchy and slow. Rather than the usual sweet dreams-themed lullaby songs, Kanye raps about how Blue Ivy and Nori will be mega powerful when they're older. It also mentions how him and Jay Z will work hard to make sure their girls have an easier path the an they did.''