The Man with the Mole

This is a mystery novel that revolves around Jack John Sperry. His father, the late Mr. Sperry, in his will, left a hundred thousand dollars in trust for Jack. Since his mother married Simeon Cairns, Jack claims Simeon is trying to ruin his relationship with his mother. An unknown person forged Simeon Cairns's signature issuing ten thousand dollars to Jack. Remington, a junior paying teller, claims that Jack did collect the money at the bank. Is Simeon Cairns trying to take Jack's inheritance by pretending to love his mother? Who impersonated Jack at the bank?