For the purposes of a fanfic I am writing I need to know how old Tyrion and Teclis are. There is no listed birthdate anywhere I can find, however by reading the books you can see some clues. For instance the twins are taken from their father to meet the Phoenix King as is the tradition for each generation of those descended from Aenarion. Even though I can't specifically remember which Phoenix King it is at the time this must be Finubar as the capital is Lothern. As far as I'm aware the capital changes for each new Phoenix King.