I am interested in the where and when Richard Mockabee and Margaret Benson, who were married in Baltimore County, MD June 15, 1837, died. I know the siblings and parents of Margaret Benson

Juanita, have you found them in census records throughout their married life? That would give you a rough idea of where they were in their old age.

“Died’” Warsaw (Illinois) Signal, 5 June 1844, 2/c.
DIED’
In Warsaw, on Thursday evening, the 30th inst., CATHARINE ANN, youngest child of Richard and Margaret Ellen Mockbee, aged 12 months and 18 days.

The Hancock County, IL 1842 tax assessment lists that Richard Mockbee had a $5 watch and $50 in "other" property. They do not appear on the 1850 Hancock County census. However, there is an Anthony Mockbee family that does show up (#803)—tailors from MD.

Joseph

Lucky, lucky, lucky.

http://listsearches.rootsweb.com/th/read/MCBEE/2007-06/11816... (6 December 2009)
5 i. Richard3 MOCKBEE was born in MD 1816. He died 1 Jul 1890 in Washington, DC. He married twice. He married Margaret E. BENSON 15 Jun 1837 in Washington, DC. She was born ca 1819. She died 8 Jun 1855 in Washington, DC. She was buried in Washington, DC. He married Delia Amanda "Dorcas" WHITNEY 7 Nov 1855 Baltimore, Baltimore, MD. She was born 1820 in MD.