With any book on Sacagawea the problem is not only getting her name wrong, but also fictionalizing her life and adding fanciful and wishful things which are not in the historical record. This is nothing new. Historical revision began over a century ago when the suffragette movement in the USA was looking for a strong female figurehead and poor Sakakawea was resurrected to fit the bill. That's when the myth-making began. No one stopped to think whether she would have wanted or supported something like that.
The fundamental truth about her is that the record is light. She's barely mentioned in the diaries that the two expedition leaders kept, and when she is, the variations in spelling are numerous making it difficult to do a search to find all the references to her. She's referred to as "the Indian woman", as "Charbonneau's squaw" (various spellings), and by the name the Hidatsa kidnappers gave to her (again with variations). That's how little regard she was given at the time.
No one bothered to record her original name or her thoughts and feelings about the journey. In that, she was treated like every other member of the expedition despite being the youngest who also happened to be carrying and expertly caring for a young baby for the entire journey. In this, she was treated as an equal to the men, so in that regard she might be considered the first recorded exemplar of equal rights in North America.
The closest we can come to her Hidatsa name is Sakakawia which means Bird (sakaka) Woman (wea). No one recorded why she had this particular name or what happened to her original Shoshone name. Native American names were very fluid, changing sometimes many times between birth and death. They were more like a current status - like something in social media - than an actual name as we in the west in modern times view names, so perhaps even Sakakawia didn't care that much what her name was.
This book along with most others, refers to her as Sacagawea which is closest to the name used phonetically in more than one spelling, in the diaries. As to her Shoshone name, no one knows what it was. A popular one doing the rounds is 'Boinaiv', but that sounds far too much like Bowie Knife to be taken seriously. Besides, as far as I know, Grass Woman in Shoshone is Ambosoni, not Bonaiv!
The next thing the books tend to do is to inflate Sakakawia's importance and contributions to the expedition by claiming, for example, that it could not have succeeded without her. I don't buy that, and neither Lewis nor Clark ever made such a claim, but this takes nothing away from the important contributions she did make, which were acknowledged by the expedition leaders.
Stoicism was an important part of Indian life. These people were tough and resilient, and Sakakawia was stoic without a doubt. She never complained, even when she was sick. She accepted what life laid before her if perhaps hoping always for something better. She obviously never wanted to be kidnapped by the Hidatsa, but she made a life with them. She more than likely didn't want to be married to Charbonneau, but she made a life with him, too.
When he signed on for the expedition, in part being allowed in because he could boast two "squaws" who spoke Shoshone, it raises the question as to why she went along when she had a newborn in tow, rather than his other wife who was referred to in later mythology as midapokawia (Otter Woman), although she remained nameless during the time of the expedition and disappeared from recorded history at that time.
But she was older with no new child, so why take the younger post-partum woman? Personally my feeling is that Sakakawia actually wanted to go on the expedition and didn't see her newborn as an obstacle. I really think she wanted the adventure and a chance of seeing her own people again, whereas 'Otter Woman' (Other Woman?!) wasn't that interested and perhaps saw this as a chance to get away from Charbonneau in his absence?
There seems to be some conflation of Otter Woman with the friend of Sakakawia's who was kidnapped at the same time as she was. That girl is referred to as Leaping Fish. I have no idea what the Shoshone for that name is, but fish is Akai. She was not Otter Woman, because Leaping (or Jumping) Fish managed to escape the Hidatsa and return to her own people. Why Sakakawia didn't go with her was never recorded. Perhaps she could not escape, didn't know about Leaping Fish's escape plan, or was recaptured. Or maybe she didn't want to escape because staying with the Hidatsa was an adventure for her - a chance to see different things. Perhaps that's why she married Charbonneau too. Perhaps she didn't escape because Charbonneau offered another distraction. We simply don't know.
So those are the facts, and this book does not embellish them inordinately. It tells a wider story, too, offering insights into life back then, into the different tribes we learn of, and so on, so it fills out the story and makes for a much more rounded reading experience. But in the end, one book about 'Sacagawea' is pretty much, of necessity, like another, because the facts don't change - only the spin an author chooses to put on them. So while I think I am done reading such books after this present flurry, I can commend this one as a worthy read.