Despite using every spelling variant I can think of, I can't find the Chissel Family in Leith (or anywhere else in the whole of the UK) on the 1861 Census.
The known details are:
George Penny Chissel, age 28/29, Gunner or Bombardier Royal Artillery, born c1832, East Allington, Kingsbridge, Devon
Ann Chissel (nee Dunn/Don) wife, age 27/28, born c1833, Stirling
George Penny Chissel, age 2, born 19th March 1859, Leith, Midlothian
Helen Chissel, age 3 months, born 13th January 1861, Hillhousefield, Leith, Midlothian
They had another son, John Chissel, also born at Hillhousefield, Leith on 2nd December 1862, so presumably they didn't hop off to somewhere else between the births of Helen in 1861 and John in 1862 ....... or did they?
I have a record of all their children's baptisms which were included in George's Discharge Papers of 1873. This shows that both Helen and John were baptised at North Leith a few weeks after their births and also their first (surviving) child George in 1859.
George and Ann were married at Stirling 2nd March 1857.
Anne