Actually our Piccolo came from an egg that King Piccolo spit out of his mouth before he died. King Piccolo is the one who split from Kami and Piccolo II is like... a child/reincarnation?
Something like that
One Namekian came to earth.
He split into Kami and Demon King Piccolo
PIccolo got sealed away.
He was unsealed by Pilaf
Havoc, dead people, destroyed Shenron
Goku kills, but as he dies, Piccolo shoots out one more egg.
Goku meets Kami, who restores Shenron and revives everyone
The egg hatches Piccolo Jr. Now just regular Piccolo.