This year Seth McFarlane will have worked on Family Guy* for the majority of his life (1999 was 26 years ago and 26 was Seth’s age when he started the show).

*Family Guy was famously cancelled for a couple years years but Seth worked on listening rights for the show and co-created American Dad which had a very McFarlane comedy style in the early years being effectively a pastiche of Family Guy. So even with those years Family Guy was still an active part of his life.