Wife Emma: in 1861, says born abt 1816 Orton on the Hill, Leicestershire
Son Walter: 1851 21 May baptism was in Over Whitacre and the WATSON Abode listed on the register was the same. The 1861 Census says he born Over Whitacre abt 1851..so it indeed looks like they should be there!
In 1841, the family address was "Quarry House" in Over Whitacre - comprising William & Emma, and their daughter Emily age 3 (not mentioned in your above list of children). A near 1841 neighbour (at least on the Enumerator Walk) was one Edward Dyke, Publican of the Owl Inn. Find
him in 1851….and find the WATSONS, next door!
and as Claire has beaten me to it

I won't repost the transcript now, but adding:
I think they
have been enumerated as WATSON in 1851, but it does look a lot like WILSON.
William's occupation: Architect & Builder, Farmer of --- acres Employing 8 men.
Baby Walter, has actually been enumerated on the sheet as "William A" age 1 month.
William's place of birth is listed as "Ansley" - the person above him is born "Arley" (compare the writing) [
these two are villages are close together and caused me grief in the past being mistaken for each other 8].
Emma's place of birth is listed as "Leicestershire Orton on the Hill", though to be fair the "Ortons on" bit is not so clear (maybe it says 'Ortons in") if you don't know that's what it's meant to be!
Cheers
AMBLY