How does one show adoptions in the family tree? Or is the adopted person omitted from the tree?
I place the word [adopted] in the Suffix box on the name edit screen. That way, the status always displays clearly, wherever you see the name, including in the Tree View.
Using the square brackets instead of parentheses avoids confusion with maiden/birth surname.
Then a reader would know to look in the main About bio for a link to birth parents, if available.
Alternatively, you could put the full name with [adopted] at the end in the "Display name as" field. So that method will then show the [adopted] part a bit more selectively, rather than in every view.