LOS ANGELES, Apr 21: Fox, the start-up broadcast network of 1987 that within a few years changed the face of U.S. Television with edgy comedy and youth programming, has finally grown up. Scoffed at from its start for setting itself up as a rival to the stodgy, old CBS, NBC and ABC, Fox celebrates 25 years on the air this Sunday with a two-hour special featuring cast reunions, re-runs, highlights and some major trumpet blowing. (agencies)