Charity by Lesley Pearse

Charity Stratton's bleak childhood is changed for ever when both her parents are killed in a fire. Separated by the authorities from her younger brothers and sister, Charity is sent out to work as a skivvy in a boys' boarding school. Her loneliness and misery are eased when she falls deeply in love with the dashing but fickle sixth-former, Hugh Mainwaring, but when she discovers she is pregnant with Hugh's baby she soon realises just how alone she really is. Determined to be reunited with her siblings and to make something of herself, Charity runs away to London and begins to forge a new life.