Your posted family tree:http://trees.ancestry.com/tree/38883323/person/19352225781
Has a lot of information that volunteer "researchers" could use to fully identify who you seek and with other criteria information such as their date of birth, etc. Some volunteer "researchers" don't actually look for information that you might already have or suggest sites that clearly won't help you.
In this case, you identified Washington Dunn was born in New York, your search should begin there. The children also were born in NY.