Brad Pitt and Angelina Jolie call each other ''Kitty'' and ''Miffy''.

The superstar couple - who raise six children together, Maddox, 11, Pax, nine, Zahara, seven, Shiloh, six, and four-year-old twins Knox and Vivienne - have given each other affectionate nicknames, with Angelina referring to Brad as ''Kitty'' and Brad calling his fiancee ''Miffy''.

A source told The Sun newspaper: ''Brad and Angelina are very lovey-dovey towards each other and don't care who sees it.''

The couple also use their nicknames to book into hotels so people don't know who's really staying there.

Before meeting Brad, Angelina used to check into hotels and make restaurant reservations using the alias ''Shiloh Baptist''.

The pair then continued to use the fake moniker while they were dating, but decided to change their secret names after their first biological daughter, Shiloh, was born in May 2006.

Angelina said: ''It's a name I always liked. I used to go under it in hotels: Shiloh Baptist. I'd gone under it when Brad used to call hotel rooms I was staying in.''