In case you don't have this:
From the 1860 US census for Newark, Essex County, New Jersey:
Name: Jane M Betts
Age in 1860: 16
Birth Year: abt 1844
Birthplace: England
Home in 1860: Newark Ward 4, Essex, New Jersey
Gender: Female
Post Office: Newark
Household Members: Name Age Occupation Born
Geo Betts, 40, porter house, England
Mary A Betts, 38, , England
Jane M Betts, 16, , England
Geo W Betts, 14, , England
Wm Spooner, 21, blacksmith, England
Source Citation: Year: 1860; Census Place: Newark Ward 4, Essex, New Jersey; Roll: M653_688; Page: 374; Image: 377
From the 1870 US census, in Newark, Essex County, New Jersey:
Name: Margaret J Sandford (Ancestry's index says "F" but I think it's a "J")
Estimated Birth Year: abt 1844
Age in 1870: 26
Birthplace: England
Home in 1870: Newark Ward 7, Essex, New Jersey
Race: White
Gender: Female
Post Office: Newark
Household Members: Name Age Occupation Born
George Betts, 50, works in saw mftry(?), England
Mary A Betts, 47, , England
Margaret J Sandford, 26, dressmaker, England
George Sandford, 5, , New Jersey
Jennie Sandford, 3, , New Jersey
Source Citation: Year: 1870; Census Place: Newark Ward 7, Essex, New Jersey; Roll: M593_881; Page: 96; Image: 194
New York Passenger Lists:
Name: George Betts
Arrival Date: 27 Jul 1850
Estimated Birth Year: abt 1820
Age: 30
Port of Departure: St Johns, Newfoundlands
Ship Name: Clipper
Port of Arrival: New York, New York
Line: 10
Microfilm Serial: M237
Microfilm Roll: M237_91
List Number: 818
Travelling with George were Mary Ann (28), Jane (5) and George (3).
According to the census, George Wells says he was a naturalized citizen. You might want to try to order a copy of his naturalization file as it will probably have marriage information in it. Here's a link to the National Archives and Records Administration online ordering website where it costs $7.50 for the file:
http://www.archives.gov/research/order/orderonline.html