Bonifazio Bevilacqua Aldobrandini
Bonifazio Bevilacqua Aldobrandini (1571 – April 7, 1627) was an Italian Cardinal.
He was the uncle of Pope Gregory XIV.
Clara Clemens
Clara Langhorne Clemens Samossoud, formerly Clara Langhorne Clemens Gabrilowitsch (June 8, 1874 – November 19, 1962), was a daughter of Samuel Clemens, who wrote as Mark Twain.
She was a contralto concert singer and she managed his estate and guarded his legacy after his death as his only surviving child.
She was married first to Ossip Gabrilowitsch, then to Jacques Samossoud after Gabrilowitsch's death.
She wrote biographies of Gabrilowitsch and of her father.
In her later life, she became a Christian Scientist.
Hysen Hoxha
Hysen Efendi Hoxha( 1861–1934) was an Albanian politician, mayor of Gjirokastër, and the uncle of Enver Hoxha.
Christopher H. Clark
Christopher Henderson Clark (1767 – November 21, 1828) was a congressman and lawyer from Virginia.
He was the brother of James Clark, the uncle of John Bullock Clark, Sr. and the great-uncle of John Bullock Clark, Jr..
Andrzej Gawroński (actor)
Andrzej Gawroński( born 10 February 1935 in Warsaw, Poland) is a Polish film and theatre actor.
He is the brother of the late actor.
He is also the uncle of, whose husband is.
Bradley Orr
Bradley James Orr( born 1 November 1982) is an English retired footballer.
He is the uncle of Rangers defender Jon Flanagan.
John Breckin
John Breckin( born 27 July 1953) is an English former professional footballer who played as a left- back.
He is the uncle of Nottingham Forest defender Ian Breckin.
Mark Twain
Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), known by his pen name Mark Twain, was an American writer, humorist, entrepreneur, publisher, and lecturer.
He was lauded as the "greatest humorist this country has produced", and William Faulkner called him "the father of American literature".
His novels include "The Adventures of Tom Sawyer" (1876) and its sequel, the "Adventures of Huckleberry Finn" (1884), the latter often called "The Great American Novel".
Twain was raised in Hannibal, Missouri, which later provided the setting for "Tom Sawyer" and "Huckleberry Finn".
He served an apprenticeship with a printer and then worked as a typesetter, contributing articles to the newspaper of his older brother Orion Clemens.
He later became a riverboat pilot on the Mississippi River before heading west to join Orion in Nevada.
He referred humorously to his lack of success at mining, turning to journalism for the Virginia City "Territorial Enterprise".
His humorous story, "The Celebrated Jumping Frog of Calaveras County", was published in 1865, based on a story that he heard at Angels Hotel in Angels Camp, California, where he had spent some time as a miner.
The short story brought international attention and was even translated into French.
His wit and satire, in prose and in speech, earned praise from critics and peers, and he was a friend to presidents, artists, industrialists, and European royalty.
Twain earned a great deal of money from his writings and lectures, but he invested in ventures that lost most of it—such as the Paige Compositor, a mechanical typesetter that failed because of its complexity and imprecision.
He filed for bankruptcy in the wake of these financial setbacks, but he eventually overcame his financial troubles with the help of Henry Huttleston Rogers.
He eventually paid all his creditors in full, even though his bankruptcy relieved him of having to do so.
Twain was born shortly after an appearance of Halley's Comet, and he predicted that he would "go out with it" as well; he died the day after the comet returned.
Ivan Benito
Ivan Benito( born 27 August 1976 in Aarau) is a Swiss retired professional footballer who played as goalkeeper.
He is the uncle of Loris Benito.
Ivan Novoseltsev
Ivan Petrovich Novoseltsev( born January 23, 1979) is a Russian former professional ice hockey winger.
He is the uncle of Vladislav Namestnikov.

Question: Who is Clara Clemens's uncle?
Answer: Orion Clemens