>>32839327FRLG game hinted that a red-haired boy was Giovanni's son. But it basically wasn't confirmed. Just an easter egg that probably wasn't supposed to be followed up on.
The FRLG manga in 2004-2006 went yolo and said that Silver was Giovanni's son. It wasn't confirmed in games at all at that point as games and manga are different continuities and people back then were skeptical that it was manga-exclusive.
Fast forward to HGSS, and wham, now everyone and their mom knows that Silver is Giovanni's son, but what they don't know is that the manga basically jumped at the idea 4 years earlier, and the remake merely adapted it, but in their own way.
