Thread necromancy! *zombies attack*
Sorry, but as I'm searching for flags I came across this gem of a topic, and I have relevant information!
According to Rebecca Kapowski's "Translation Junk Drawer" page, Tyler was originally supposed to be Odin's (Tylon's) descendant. Check it out:
http://www.sceneryrecalled.com/trans/ps.htmIt's under the description for the link to
Phantasy Star I, II, and II "Best Character" Ranking. She says the information about Tylon/Tyler appears in
The World of Phantasy Star, so at one point Sega did consider making these two characters related.
I personally consider them ancestor/descendant, 1) because it's interesting, 2) because all the characters from PSI
except Odin are given some kind of post-game history and tie-in to the other games.