In medieval Europe, were children born in an annulled marriage automatically illegitimate?

Question

I know that under modern laws (even within the Catholic Church), children born in a marriage that is later annulled are still considered legitimate, because they were born of a putative marriage. Was that also true in the Middle Ages? "Bloody" Mary and Elizabeth were both declared illegitimate and then legitimate several times, if I understand correctly, but was that the necessary result of annulment, or just their father's decree so he could choose his successor?

Answer 1

In the case of Henry VIII and Katherine of Aragon, Henry was trying to go beyond a conventional annulment to argue that the marriage should not have been allowed in the first place as Katherine had been married to Henry's brother Arthur. Keep in mind, that Henry's marriage to Katherine had required papal dispensation in the first place.