X00369: Investigating Ellen Rothwell

Last week, I mentioned ordering the potential birth and death records for Ellen Rothwell from the General Registry Office. When I had a look at the potential death registations, however, I found this for the 1851 record:

ROTHWELL, ELLEN
GRO Reference: 1851 M Quarter
BLACKBURN
Volume 21, Page 45
Age at Death: 85

With an age of death of 85, this can't be the Ellen Rothwell born in 1842. So I had a look at some other records that might fit and found two potential records:

ROTHWELL, ELLEN
GRO Reference: 1844 J Quarter
BLACKBURN
Volume 21, Page 19
Age at Death: 2

and

ROTHWELL, ELLEN
GRO Reference: 1846 D Quarter
BLACKBURN
Volume 21, Page 39
Age at Death: 5

The first one would suggest a birth year of 1842, which matches. The second one is close, with a birth year of 1841. I'm going to order the first certificate and see if it gives any clear indication that this is the correct person