|Information in this article is non-canon|
|Color:||light grey colored wings; orange body|
|Debut:||The Land Before Time XV: The Friendly Sharptooth Flyer|
Sydo is the father of Ptero and the husband of Agatha. He marreid a Sharp Beak, for which he got banished from his herd for. He was happily married for some time, but things went south when his Sharptooth mate wanted their boy Ptero to be a Sharptooth as she wanted him to lead the pack after her and she wasn't willing to let Ptero choose. Sydo had had enough and was going to take off the next morning with Ptero.
However, Ptero accidentally let slip to Agatha of the plan, without even realizing it, and Agatha lured her mate away and killed him. She then framed his death on Sydo's old herd.
However, in the end, Sydo had the last laugh as Ptero ended up finding Leaf Eaters anyway and finding his Flattooth heritage.
- Sydo was the first good character to die since Littlefoot's Mother died in the first movie.