NameJulia H Potee 
Birth1827
Memo(cemetery listing)
Death1881
Memo(cemetery listing)
BurialFriends Cemetery, Baltimore, MD
Parent-Proof notes for Julia H Potee
Julia H Potee was consistently listed in the 1850-1880 Census, always with Peter P Potee.
Peter P's age was reported as 39, 48, 60 and 70 in 1850/1860/1870/1880 respectively. Hers was given as 23/28/37/60. Peter and Julia are buried side by side at the Friends Cemetery in Baltimore. Her death certificate shows her as single (married and widow or widower are crossed out). It seems clear Peter P and Julia were brother and sister.
Her death certificate also tells us she died 14 Jun 1881 at age 60 (no months or days filled in -- so perhaps just an estimate). These dates are contradicted by her vitals as given in an online Friends Cemetery index which shows her born 2/?/1827 and died 6/11/1881. (Peter too is listed in this index but no dates are given for him.)
A reading of the explanatory notes to that on-line index makes it clear that most of the stones in this cemetery are very hard to read. From the transcription, I believe her tombstone actually shows the day in February that she was born but was too badly eroded and couldn't be made out.
So, I have gone with her death certificate as definitive as to the dates. I can easily understand how June 14 could be mis-read as June 11. And similarly, I can see how 1821 could be mis-read as 1827.