Some TMNT stuff really isn't for little kids.
In the IDW continuity, the First Herd was the previous iteration of the Triceraton race. They met their end in the service of Utrom leader Quanin, who sent the entire force into a space battle only for them to be annihilated. The one and only survivor of the race was Zog, a young child. He was raised by Utroms and groomed to be leader of a newly reborn Triceraton race, the Second Herd, who were all gradually cloned from the DNA of the First Herd.
Though the First Herd technically still existed as long as Zog was alive, he was raised and molded to lead the Second Herd, and the First Herd became a topic of history now passed.
- Zog's father (deceased)
- Zog's mother (deceased)