Here's what I have on your great grandfather Richard. I'm still trying to learn more about his father Dennis Dwyer. I also have a g-great grandfather named Dennis Dwyer. He may be the same as yours:
Richard Hugh Dwyer was born in Endeavour, Manchester, Jamaica on 11/18/1852. In Manchester, Jamaica, he was baptized on 2/18/1853. His parents were Dennis Dwyer and Elizabeth Dwyer. He had six brothers (Dennis Saunders Dwyer (4/8/1839), James Blake Dwyer (1844), Charles Waugh Dwyer (6/9/1846), William Abner Dwyer (12/13/1850), George Dennis Dwyer (1859), Henry Gordon Dwyer (12/7/1861)) and four sisters (Sarah Elizabeth Dwyer, Eleanor Maxwell Dwyer (1840), Emma Maria Elizabeth Dwyer (7/17/1857), Sophia Ann Caroline Dwyer (1/17/1865)).
When he was 46 years old, his mother Elizabeth Dwyer died (1/5/1899).
On 4/18/1900, he married Susan Elizabeth Williams Josephs (1854) in Manchester, Jamaica. He was 47 years old when he married Susan Elizabeth Williams Josephs, who was 45 years old at that time. He had ten children with Susan Elizabeth Williams Josephs: Richard Hugh Dwyer (1/17/1879), Susan Adella Dwyer (1/17/1879), Agnes Jane Dwyer (10/25/1880), John Dwyer (8/21/1882), Alice Maud Dwyer (10/18/1884), Florence Beatrice Dwyer (1887), Dwyer (12/6/1888), Dwyer (5/15/1891), Dwyer (5/7/1893), Dwyer (11/27/1895).
He worked as a Carpenter in Jamaica.
On 6/13/1931, he died in Mile Gully, Edeavour, Manchester, Jamaica when he was 78 years old. His wife Susan Elizabeth Williams Josephs died on 12/9/1898, 33 years before him.