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I am looking for the descendents of my grandfathers first family. He was married twice and my father has five siblings he has never met, nor will he as they are all likely to be dead by now. But their children and grandchildren, etc, should still be around.
William Marsden was born at Earnshaw Bridge in Leyland, Lancashire, UK in 1876. His first wife was Maria Catterall born in Brookfield, Leyland in c1877. By the 1911 census they had had eight children but only five had survived. These five were : - Eva 1896 born in Leyland, Thomas 1897 born in Leyland, Ada Alice 1901 born in Penwortham, Lancashire, James 1904 born in Penwortham,and Victor William 1908 born in Leyland. By 1911 the family were living in Bankfield Street, Bolton. One of the boys became a teacher at the Haslam Park school and taught my uncle. It turns out that he knew he was teaching his half brother but never said anything. My uncle only found out years later. Can anyone please help?

have you searched for the children's marriages at freebmd ?

http://freebmd.rootsweb.com/cgi/search.pl

once you find a marriage then you can search for births to the marriage with the surname and mother's surname

that would result in people born in the 1920s and 1930s probably so too recently to put their details here as they might be living

you can then search for their marriage ... some could be too recent for freebmd of course but the index at Ancestry can be searched, you can take out a 14-day free trial for that

as you go along you will have more names to search for in family trees here at this website and add to your tree

for example since the family was in Bolton

Marriages Dec 1915
Marsden Eva Price Bolton 8c 654
Price Harry T Marsden Bolton 8c 654

and there are births in Bolton in 1916, 1918, 1924, 1927

only the certificate would show for sure whether that was the right person but you could use it as a working theory

of course you also need to verify the children's ages since census ages are not accurate, for searching family trees at this website ( although many people do use census ages in their trees so always search plus or minus two years or more )

Births Jun 1895
Marsden Eva Chorley 8e 536

not 1896, Leyland was in Chorley registration district