Could you please list the names of all his children, as it might help us research (that being dependent on whether John & Charlotte followed traditional naming patterns).
I also just want to note that on the 1841 census, John's return says that he was not born in county, so we are looking for a birth outside of Middlesex.
Queenie 
John and Charlotte had the following children:
William John Lloyd born 26 Jan 1795 Westminster possibly died 1807 Margate, Kent??
Charlotte Lloyd born 6 Aug 1796 Westminster died?
Henry Lloyd bap 30 Sep 1798 St James Westminster m Caroline Jane Bessell 27 May 1822 died 18 Mar 1867 Geelong, Victoria
Mary Ann Lloyd born 23 May 1800 married James Jones 13 Jul 1817 died 1864 London
Eliza Alice Woof Lloyd bap 10 Jan 1804 St Luke Chelsea died 30 Dec 1878 Chelsea
Leonara Lloyd bap 8 Dec 1805 St Luke Chelsea died 1874 Chelsea
John Lloyd born 23 Jan 1808 Chelsea m Caroline Deacon 5 Nov 1830 died 25 April 1889 Richmond, Victoria
Caroline Chipps Lloyd bap 13 Feb 1811 died 1874 Wandsworth