In the novel Death on the Nile, Melhuish Ridgeway was the father of Linnet Doyle and the husband of Anna. His business speculations almost made Ned Robson go bankrupt.
Ridgeway and Andrew Pennington were lifelong friends, and Pennington described him as a "very remarkable man", as well as a very successful man. Pennington also mentions how proud Ridgeway used to be of his daughter, Linnet.
On Ridgeway's death, Pennington was appointed business guardian to Linnet, and was one of the trustees to the vast fortune she inherited. His partner, Sterndale Rockford, was also a trustee. Two other trustees were also appointed, but they had passed away before the events of the novel, and their names are not mentioned.