I know, I felt the same, didn’t quite seem right. I started to suspect he might be a clone. But then I read this...Not sure I was happy with Grogu's backstory.
I also think the Ahsoka V Thrawn will be tied in with her own series.
The Child is a member of the same alien species as the Star Wars character Yoda. He is 50 years old during the events of The Mandalorian, but still appears to be an infant because of the pace at which that species matures