1.  Marriage Index:  Maryland, 1655-1850.  Liahona Research, Orem, UT (Broderbund CD-224):

Syas, Jacob

Hinton, Margaret Ann

27 Jun 1840

Frederick Co.

2.  1850 Census Index/Images (online at Ancestry.com; Image #52-53 of 90):  Middletown Election District, Frederick Co., MD, pp. 336B-337A, 369/381, enumerated 24 Jul 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):

Jacob Syas/Syes	36	M		Labourer	350	Md
Margaret A   "	27	F				"
Richard H    "	9	M				"
Mary A M     "	5	F				"
Susan F      "	3	F				"
Charlotte E  "	5/12	F				"
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Maria E Bell	19	F				Maryland

Living next to presumed mother, Widow Susan SYAS, and presumed brothers, William H. SEYAS and Samuel SEYAS. 

3a.  1860 Census Images (online at Ancestry.com; Image #46-47 of 68):  Middletown P.O., Middletown Dist., Frederick Co., MD, p. 274-275, PN 86-87, 604/639, enumerated 26-27 Jun 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):

Jacob Syass	40	M		Carpenter		50	Md
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Charlotte Syass	9	F					Maryland
Richard    do	20	M					"
Susan      do	70	F					"

3b.  1860 Census Images (online at Ancestry.com; Image #34 of 83):  Frederick P.O., Frederick Dist., Frederick Co., MD, p. 782, PN 230, 1715/1759, enumerated 17 Jul 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen).  For full record, see David MILLER's family group sheet. 

David Miller	36	M		Farmer	13,000	4,000	Md
[David's wife and children]
Susan Sias	12	F					"
[hired help]

Why is Susan outside her home?  Were they so hard up that she had to be hired out?