Wilkie Collins met Charles Dickens on 12 March 1851 in the amateur production of Bulwer Lytton's play Not So Bad as We Seem. Although Dickens was twelve years older and an established author and public figure, a lifelong friendship followed. They dined together, took holidays together, and visited the less reputable parts of London and Paris together. They also worked together. He collaborated with Dickens on several Christmas issues of both publications.

    Perhaps because of their friendship, Collins did not put Dickens in the pantheon of novelists. That honour he reserved for James Fenimore Cooper, Walter Scott, and Honoré de Balzac. His first recorded honour to Dickens was the dedication to his third published novel Hide and Seek in 1854. In 1860 Collins had referred to Dickens in the preface to the three volume edition of The Woman in White.

    In later years, shortly before Dickens's death, relationships between them were, for a while, strained. One possible reason is that Wilkie's brother Charles Allston Collins had married Dickens's daughter Kate. Charles was a sickly man to whom Dickens took a growing dislike as they both headed towards the grave. After Dickens's death our knowledge of Collins's feelings about him come from some marginal notes he made in Forster's The Life of Charles Dickens. They were discovered when Collins's library was sold after his death in 1889.
 

More information:

Letters of Charles Dickens to Wilkie Collins
 

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