The world of Family Guy is filled with a rich variety of characters, and Seth MacFarlane lends his voice to more than his fair share of them. Although he's famous for portraying key members of the Griffin family, that's not where his role ends. A talented and flexible voice actor, MacFarlane is capable of completely transforming how he sounds, and he uses this ability to its fullest extent within his work. His ability to hit all emotional levels also adds an extra layer to the feel of the show. For instance, some of the worst things Stewie Griffin has ever done are also some of the funniest scenes because of MacFarlane's acting.

https://screenrant.com/family-guy-seth-macfarlane-best-characters-voiced-ranked/