In New York City is the family of a Patrick Dowling age 32 laborer born in Ireland. Wife Margaret age 28 born Ireland, son John age 7 born England (?), daughter Mary A. age 5 born New York, son Michael age 2 born New York, daughter Margaret age 3 months born New York. Living next door, per the census, is a James Dowling age 21 born Ireland and next door to his household is Richard Grogan age 40 and wife Bridget age 35 and their children Mary and Joseph. Of note is that ancestor Patrick Dowling had a daughter Catherine that was first married to a Mr. Grogan.

1880 Census: 
Jacksonville (Morgan) IL, P.D. Dooling age 54 born Ireland as were parents, working in brickyard, wife Mary age 54 born Ireland as were parents, son Thomas age 22 born IL workiong in brickyard, daughter Catherine age 17 b.IL, daughter Mary A. age 14 b.IL, son Cornelius age 11 b.IL, William age 4 b.IL 
Cherry Valley (Winnebago) IL, Patrick Dowling farmer age 55 born Ireland as were parents, wife Ann B. age 51 born Ireland as were parents, daughter Mary age 22 born NY, son James age 20 farmer b.IL, son John age 18 farm laborer b.IL, daughter Annie age 15 b.IL, daughter Katiz age 11 b.IL, daughter Sarah age 10 b.IL 
Rock Falls (Whiteside) IL, Patrick Dowling age 55 laborer born Ireland as were parents, wife Margaret age 50 born Ireland as were parents, daughter unnamed age 25 gardener born Ireland 
Kansas City (Jackson) MO, Patt Dowling age 40 hostler born Ireland as were parents, wife Mary age 30 born Ireland as were parents, Suzzie Maffit age 12 servant born NY, John Welch age 30 laborer born Ireland, Tom Lynch age 20 laborer born Ireland 
New York City, Patrick Dowling age 43 laborer born Ireland as were parents, wife Margaret age 38 born Ireland as were parents, six children all born in NY: John age 17, Mary age 14, Michael age 12, Margaret age 10, Patrick age 7, Thomas age 3 
New York City, Patrick Dowling age 35 butcher born Ireland as were parents, wife Ann age 35 born Ireland as were parents, four other people of a different family were also living in this household 
Syracuse (Onondaga) NY, Pat Dowling age 35 coachman born Ireland as were parents, wife Sarah age 29 born Ireland as were parents, daughter Maria age 5 born NY, son Ed age 9 months born NY 
Brooklyn (Kings) NY, Patrick Dowling age 46 laborer born Ireland as were parents, wife Christina age 40 born Ireland as were parents 
Adams county IL, Patrick Dowling age 40 carpenter  born Ireland as were parents, wife Sarah age 35 born Missouri father born VA mother born Kentucky, five children all born in IL: Mary age 13, Catherine age 9, Julia age 7, Agnes age 5, Edward age 2. Also living in the household were Sarah Whalen age 63 born Ireland and Edward Dowling age 30 laborer born Ireland

TO FIND: Immigrant Ancestors, Wife (nothing known about her), Birth/Death Date/Place, Censuses (NOTE: Unknown if he ever lived in the U.S.) 

Unknown if he ever migrated to the United States from Ireland. If not, then when/how did his daughter Catherine get to the U.S.

Historical
1838-1840: Central America - Civil war in the Federal Republic of Central America led to the foundings of Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica
1839-1851: Uruguay - Uruguayan Civil War
1839-1860: France, England, United States, Russia, China - After two Opium Wars, France, the United Kingdom, the United States and Russia gained many concessions from China resulting in the decline of the Qing Dynasty
1840: New Zealand, England - New Zealand is founded, as the Treaty of Waitangi is signed by the Ma-ori and British
1844: Haiti - Dominican War of Independence from Haiti
1844: Iran - Persian Prophet the Bab announces his revelation on May 23, founding Babism, he announced to the world of the coming of "He whom God shall make manifest", he is considered the forerunner of Baha u llah, the founder of the Baha I Faith
1844: United States - First publicly funded telegraph line in the world, It is between Baltimore and Washington and sends demonstration message on May 24, ushering in the age of the telegraph, this message read "What hath God wrought?" (Bible, Numbers 23:23)
1844: United States - Millerite (followers of the teachings of William Miller) movement awaits the Second Advent of Jesus Christ on October 22, the non-appearance of Christ becomes known as the Great Disappointment
1845-1846: Pakistan - First Anglo-Sikh War in Punjab (Pakistan) between the Sikh Empire and the British East India Company
1845-1849: Ireland - The Irish Potato Famine led to the Irish diaspora
1845-1872: New Zealand - The New Zealand Land Wars
1845: Tonga - Unification of the Kingdom of Tonga under Ta-ufa?a-hau (King George Tupou I)
1846-1847: United States - Mormon migration to Utah
1846-1848: United States, Mexico - The Mexican-American War leads to cession by Mexico of much of the modern-day Southwestern United States
1847-1901: Mexico - The Caste War of Yucatan
1848-1849: Pakistan - Second Anglo-Sikh War in Punjab (Pakistan) between the Sikh Empire and the British East India Company, this war basically ends the Sikh Empire
1848-1858: United States - California Gold Rush
1848: Europe - Revolutions of 1848 in Europe as some type of revolution occurred in most all European countries (except England and the Netherlands), the revolutions were quickly put down as they were mostly unorganized peasants
1848: Russia - The Communist Manifesto published
1848: United States - Seneca Falls Convention is the first rights for women convention in the United States and leads to the battle for suffrage and legal rights for women
1850: Europe - The Little Ice Age ends around this time
1851-1852: South America - The Platine War (also known as the War against Oribe and Rosas) fought between the Argentine Confederation and an alliance consisting of the Empire of Brazil, Uruguay and the Argentine provinces of Entre Rios and Corrientes, the war was part of a long-running contest between Argentina and Brazil for Influence over Uruguay and Paraguay, and hegemony over the regions bordering the Rio de la Plata (River Plate), the conflict took place in Uruguay, on the Rio de la Plata and in the northeast of Argen
1851-1864: China - The Taiping Rebellion in China is the bloodiest conflict of the century
1851-60s: Australia - Victorian gold rush in Australia
1851: England - The Great Exhibition in London was the first International Expo or Worlds Fair
1853-1856: Ukraine, France, England, Turkey, Russia - Crimean War between France, the United Kingdom, the Ottoman Empire and Russia
1854: Japan - The Convention of Kanagawa formally ends policy of Isolation by Japan
1855: England - Henry Bessemer Invents a process that enables steel to be mass produced from molten pig Iron
1856: Romania - First oil refinery in Romania
1857-1858: India - Indian Rebellion of 1857 (also known as First War of Independence for India, the Great Rebellion, the Indian Mutiny, the Revolt of 1857, the Uprising of 1857, the Sepoy Rebellion and the Sepoy Mutiny), It began as a mutiny of native soldiers (sepoys) employed by the British East India Company's army
1859: England - Charles Darwin publishes "The Origin of Species", It is a work of scientific literature considered to be the foundation of evolutionary biology, Its full title is "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life", It presents a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution and Includes evidence Darwin gathered on the Beagle expedition in the 1830s and his subsequent findings