The obituary just posted PROVES that the Mary who was the wife of William Lowe in Green County, Wisconsin in 1850 has a maiden name of Sanderlin. The Mary Lowe Merrick in the obituary matches the census in both 1850 and 1860. She was "born in Albany, Wisconsin," which is in Green county, Wisconsin - which is where the William and Mary Lowe family lived in 1850.
It is nowproven that David Lowe was the son of William Lowe and Mary Sanderlin.
The biography of Mary Lowe Merrick says she moved "with her parents" to California and she grew up in El Dorado [in El Dorado county], California. Perhaps in 1860 William is not with his family because he moved out to California ahead of them, to get settled? On the other hand, he may have died before 1860. Then his wife Mary may have remarried and moved with the new husband and her children to California. For that matter, Mary could have moved to California before remarrying, to be near her son Joseph (who was already out there in 1860) and then remarried. In other words, the reference to "parents" could refer to a step-father. Needs more research.
In a quick search I did not find a William Lowe born about 1805 in a California census.
Here's that 1850 census, Green County, Wisconsin, AGAIN:
1850 Mount Pleasant, Green, Wisconsin William Lowe 45 b about 1805 Virginia Mary Lowe 43 b about 1807 Virginia Benjamin Lowe 18 Joseph P Lowe 16<---------------see 1860 census below David Lowe 14 b abt 1836 Ohio Sarah Lowe 12 William H Lowe 10 John C F Lowe 7 Cyrus Lowe 5 Mary E Lowe 1
In 1860 Joseph P Lowe born about 1834 is not with the family; he is grown and gone. This must be him:
1860 El Dorado County, California J P Lowe age 26 Mary Lowe 21 b Wisconsin Ernest Lowe 5
The above census fits with the biographical material posted by descendant Marion, the family historian with so many posts (our angel - a name I've been adding to clarify who I mean).
I've now found an Ancestry.com family tree for Susan Sanderlin, born 1852. She married in Green County, Wisconsin. The name of the tree is Canfield-Buck Limited. Miles, since you have a subscription, you have access to that tree. It also includes the Lowe family.