Abbreviation "Do" used in Orphans Court documentation early 1800's
Does anyone know what an abbreviation that looks like "Do" ("O" is smaller and up higher next to "D") means? I've come across it in an accounting document attached to an orphan's court case. See right hand page under heading of "Document B" in the following image.
Also, if anyone is able to transcribe the word in sentence under heading "Document B", that would be super helpful as well. It makes sense to me that the word says "Legatees" but the first two letters really look like an "Sr". which is confusing me.
Thank you to anyone that can help me!!