Hi again. As far as I can see Shipton on Stour is also known as Shipston on Stour and is in Warwickshire (though only just, it is right over the border from Goucestershire and not very far from Worcestershire).
Benjamin was born about 1866 but there is no way of telling where his parents were in 1861, it might have been Shipton and then again it might not.
If you want Benjamin's father then I still think the 1871 census for Middlesex is your best shot since Sarah was born there in 1868 and Frederick in 1873.
Having said that I just looked to see where births register for Shipton on Stour and here is what it says at
http://www.fhsc.org.uk/genuki/REG/war.htm#shipShipston on Stour
Created 1st July 1837. Mainly in Warwickshire, but included parts of Gloucestershire and Worcestershire.
Sub-districts : Campden; Halford; Moreton; Shipston on Stour.
GRO volumes : XVI (1837-51); 6d (1852-1930).
So I think it is possible that Benjamin was born in the bit of Worcestershire which registered as Shipston on Stour. Very confusing and not a lot of help! Though you could try locating his birth certificate.
Try a request for Middlesex 1871 first, include the 1881 data so that people can see where all the children were born (that way if they don't show up in Middlesex then they can look in Gloucestershire and Worcestershire too). Good luck!
