I’m from [name]CA[/name], but have lived in NYC forever. I realized that I pronounce it differently for different contexts as a pp mentioned:
[name]Prince[/name] [name]Will[/name]-yim
[name]Will[/name]-ee-um Shatner
You could skip all this and name him [name]Willem[/name], like [name]Willem[/name] Defoe:) ha ha! I think the general US pronunciation is [name]Will[/name]-yum, but it all depends on your preference. [name]Even[/name] my mom’s parents pronunced her name differently all her life (my mom’s name is “[name]Marcia[/name]” (pronounced [name]Mar[/name]-see-a, not [name]Marsha[/name]) but her dad proununced it
"Marss-i-a)…so go figure:)