User blog comment:RocksisDragonOP/Rocks D. Xebec IS MONKEY D. DRAGON/@comment-93.25.183.247-20200503111243

Remember :

1) Roger is only a year younger than Garp and the fight where they deafeated the rocks pirates is supposed to be when they were young,

2) White beard was a part of that fight, till as a part of Rocks pirates.

3) Rocks Pirates were supposed to be the bosses of an era so they should have been at the top level for some years already beafore they were defeated.

Since Roger was at the end of his life at his late 40ties and his 50ties, so even assuming that the fight against the Rocks took place only a few years before him turning 40, it would mean that Dragon was a less than 18 years old pirate era leader.

Conclusion : being the son of Garp with a 23 year gap it makes it very tight for Dragon to be Xebec