Yep, you read that right. The Groot we see in Guardians of the Galaxy Vol. 2 is not the Original Groot from Vol. 1 but his son! James Gunn confirmed the new identity after weighing in on a debate about which alien he prefered: Porgs or Groot and which one he would save from death if he could only save one. Naturally, he chose Groot!
There. The original Groot is dead. Long live baby Groot.