Seems llike you are copying and pasting from online trees and not researching at all........... research means finding real records and proving each and every person "Katherine of Berain " Katherine Tudor's parents were Robert Vychan/Jane Velville however you need to prove each and every person from you back 500 yrs and I KNOW you have not done that
You could message the person who has those individuals on their tree and ask them for sources. If the source is "Ancestry Family Trees", they are suspect. The biggest mistake people make in our little hobby is assuming all Ancestry users are careful researchers. Some of them are, but others don't even have common sense, let alone research skills. If you poke around, it won't take you long to find people dying in 1881 and appearing on the census in 1900. There are other mistakes.