Hi Kinkers and welcome to Rootschat. Working on your know info am I right with the following. Your Thomas jnr died 1903 in Victoria, Australia, aged 66 giving a dob of 1837. I have found a Thomas Duckworth born 14th October 1837 in Bangalore, India.His parents are however Thomas ( his occupation given as Apothecary both at his marriage and the baptism of son)and Sarah nee' Boot.
Sarah Duckworth nee' Boot died 27.11.1843 aged 31 and recorded as wife of assistant apothecary Duckworth.
Thomas Duckworth aged 49 died 10.6.1858 Bangalore occupation--pensioned Apothecary
I know the 1903 death records a mother Ellen Davis, did she marry Thomas snr after death of Sarah. Thomas jnr would only have been 5 at the time of mother's death.
SS