Template talk:The Tudors of Penmynydd
Any material lacking a reliable source directly supporting it may be removed and should not be restored without an inline citation to a reliable source. Whether and how quickly material should be initially removed for not having an inline citation to a reliable source depends on the material and the overall state of the article. In some cases, editors may object if you remove material without giving them time to provide references; consider adding a citation needed tag as an interim step.
Unlike an ordinary navigation template, ancestry trees contain information that is not covered by sources in the individual articles to which they link. For example which of the two articles contains a source that clearly states that Ednyfed Fychan is related to Goronwy ap Tudur Hen as this tree purport to show. Even if this could be worked out by visiting each article in turn, that still would not meet the requirements of WP:V as it would be either using a wikipedia page as a source or synthesis of facts.
A tree like this does not need a citation on every node depicting the relationship with everyone to whom they are connected. As a parent can have many children, it is often simpler just to include a verification of parents in the child node as biographies usually include parents even if they do not include all the children, and all biographical facts such as parents in an article ought to be fully supported with citations.