Hughes, pictured as a baby, chose to live in America, his mother's country
Nicholas Hughes, the son of poets Sylvia Plath and Ted Hughes, has killed himself at the age of 47.
The couple's other child, Frieda Hughes, told the Times newspaper that her brother had been battling depression for some time.
Hughes had been working as a professor in Alaska. His sister paid tribute to "a loving brother, a loyal friend to those who knew him".
Plath took her own life in 1963 when her two children were infants.
The writer also had a history of depression and her novel, The Bell Jar, is one of the most acclaimed depictions of the disease.
She gassed herself while Nicholas and Frieda lay in the room next door. Her suicide note was left pinned to the children's pram.
Her death led to criticism of Plath's husband Ted Hughes, who had recently left the family for another woman.
Ted Hughes later wrote of his concern over the effect on his children of the circumstances of her death.
Frieda Hughes highlighted the closeness of the relationship between father and son in her statement to The Times.
Nicholas Hughes was an evolutionary ecologist. His sister said: "His lifelong fascination with fish and fishing was a strong and shared bond with our father (many of whose poems were about the natural world)."
She explained that he had recently left his job as professor of fisheries at the University of Alaska to "advance his not inconsiderable talent at making pots and creatures in clay".
She added: "Despite the vagaries that life threw at him, he maintained an almost childlike innocence and enthusiasm for the next project or plan."