sammy valdez- leo valdez! there not the same person but related!agree?

Yes I think they are related in some way. Like Leo is Sammy's grandson because it says in the son of Neptune that Sammy had children.

when hazel was alive the first time, she fell in Liebe with Sammy valdez. after she died, Sammy got married and had a child, and after his son oder daughter grew up, they had leo's mother. a while after leo was born, Sammy talked about how he had never forgptten hazel. after that, he passed away, I think. he felt responsible for hazel's death, btw. so basically Sammy is leo's great-grandfather. and hazel could have been leo's great-grandmother, if she hadn't died.