One Direction's Louis And Mystery Girl

See the photo of Louis from One Direction leaving Niall's birthday party with a mystery girl.

The 'What Makes You Beautiful' boys were partying in London for Niall's 18th, and it looks like Louis got lucky.

He was spotted leaving the party with this pretty brunette, as seen in the picture below, who spies at The Sun say is a girl called Eleanor Calder.

And Louis' new girl could already be mates with his mum Johannah Tomlinson after it appears she and Eleanor recently made friends on Facebook.

Meanwhile the band are releasing a new book 'Dare To Dream: Life As One Direction', in which Louis reveals his plans for a massive family.

"I definitely want kids one day so I can have that little boy I always wanted," Louis confesses.

"I could end up with 15 to 20 kiids if I don't have a son straight away. Something to be aware of, I guess, for anyone wanting to marry me."

One Direction's new song 'What Makes You Beautiful' is out to buy and download now after hitting the Vodafone Big Top 40 No. 1 on Sunday.

One direction Louis