1920 James F. Donegan 48, parents born in Ireland Laura 46 William 19 George 15 James 6
1910 James Donegan 39 (married 12 years) Laura 36 William 9 George 6
1900 James Dunegan, born Feb 1872 Laura, born Aug 1873 William, born May 1900
1880 M. C. Donigan 36, born Ireland Margaret 36, born Ireland George 12 James 8 Eugeon (Eugene?) 5 Richard 1
1870 Margt Donigan 26 M. C. 26 Geo 2
1900 George Donegan, born Aug 1867 Margret, born April 1872 Flora, born May 1892 Marie, born June 1896 Matthew, born Jan 1846, widowed father
1910 Same family, shows Matthew immigrated 1860, born Ireland
1920 Same family, except George is now widowed
1930 Same family except without Matthew.
Some of these records you can look at for free at labs.familysearch.org and Ancestry.com. For those you cannot see for free I suggest checking with your local libraries to see if they have Ancestry or Heritage Quest.
If you are still looking for more I suggest getting the death certificates and obituaries. If they died after Jan 1, 1906 you can try to get the death certificate directly from the PA Div. of Vital Records. The Philadelphia Free Library and the Historical Society of Pennsylvania may be able to help you with the obits. The Philadelphia Family History Center may also be able to help you.