This is the only John Parr born Suffolk circa 1800 showing up on the 1861 census. Don't know if it is your John, though, because wife's name doesn't fit.
Paradise Row
John Parr 1799 Newmarket, Suffolk, England Head, Brewer
Lucy Parr 1797 Lidgate, Suffolk, England Wife
Charles Rowlinson Lodger Age 20 Stableman born Newmarket
Joseph Roderigo Age 27 Stableman bornNewmarket
Lovely address except that the next address is Workhouse Yard!
RG9/1031 Newmarket Cambs Folio 120 Page 15
Do you have any more inform re Harry??
Tricia