I have a friendly letter from Oscar Quirarte of Monterrey, Mexico, who says
Manuel also was first cousin once removed of Isabella and Maria because Manuel and Queen Isabella of Castille were first cousins through John of Portugal and Isabel of Barcelos.
Manuel was double first cousin twice removed of Eleanor of Habsburg. Isabella of Castille ( maternal grandmother of Eleanor) and Manuel were first cousins) Also Manuel and Maximilian I (paternal grandfather ot Eleanor) were first cousins throug Eduardo I of Portugal and His Wife Eleanor of Aragon.
Also Manuel and Eleanor were second cousin twice removed because Manuel and Maria of Burgundy (paternal grandmothers of Eleanor) were second cousins.
John VI of Portugal and Charlotte were Second cousins through Phlip V and Isabel of Farnesio as Great Grand Parents.
Peter of Brazil and Maria Leopoldina were Second cousins through Charles III of Spain and his wife Amalia of Saxony who were second cousins once removed.
Also Queen Victoria and Prince Alberto were half third cousins twice removed through Adolphus Frederick II Duke of Mecklenburg-Strelitz
I am so grateful for his interest. If anybody would like to respond, write me here at firstname.lastname@example.org and give me permission and I’ll post it, hoping we can continue the conversation.