A SPECIAL Mass for Madeleine McCann will be said in Liverpool tomorrow ' to mark the fourth anniversary of her disappearance during a family holiday in Portugal.

It will take place at 7.30pm at Our Lady of the Annunciation, Bishop Eton, in Woolton Road, Childwall ' the parish church of Liverpool-born Kate McCann's parents, Brian and Susan Healy, and also the church where Kate and her husband Gerry got married.

Each Sunday the church holds a children's Mass at which Madeleine is remembered.

Her grandmother, Mrs Healy, said: 'The support we have had from our parish priest Father Desmond Keegan has been solid all along. Whenever we have needed his help he has been there.

'He is leaving the parish soon and moving to Edinburgh and we want to say he's been absolutely tremendous.'

Meanwhile Kate McCann's 384-page book ' Madeleine ' is being published on May 12, her daughter's eighth birthday.

Mrs Healy said: 'Kate has to tell her story, even though it's been the most terribly painful process over the last nine months. We just hope that something will come from the book. It's something that may just force someone to come forward. It's also an account for Madeleine and for the twins (six-year-old Sean and Amelie).'

Transworld won the rights to publish Kate's account of how her daughter vanished during the 2007 holiday and the subsequent efforts to find her.

When the deal was announced Kate explained: 'There are several different reasons as to why I finally came to the decision with my husband Gerry to write and publish this book. Many factors needed to be given thorough and careful consideration, not least the impact of such a book on the lives of our three children. My reason for writing it is simple; to give an account of the truth.

'Publishing this book has been a very difficult decision and is one that we have taken after much deliberation and with a very heavy heart.'

But she also stressed with 'the depletion of Madeleine's Fund (Leaving No Stone Unturned Ltd) it is a decision that has virtually been taken out of our hands'.

She added: 'Every penny we raise through its sales will be spent on our search for Madeleine. Nothing is more important to us than finding our little girl.'

And Gerry McCann said: 'Our hope is that it may prompt those who have relevant information (knowingly or not) to come forward and share it with our team. Somebody holds that key piece of the jigsaw.'

The publishers have secured an exclusive serialisation deal with a national newspaper group.