You are both right. The Aust. Dict. Biog. says:
LA TROBE, CHARLES JOSEPH (1801-1875), superintendent and lieutenant-governor, was born on 20 March 1801 in London, the son of Christian La Trobe and his wife Hannah, née Sims. His family was of Huguenot origin. His great-great-grandfather, Henri Bonneval La Trobe, had left France after the revocation of the Edict of Nantes to join the army of William of Orange and arrived in England in 1688; after being invalided out of the army he settled in Dublin and from there his grandson Benjamin went to England to train as a clergyman in the Moravian Church. Christian Ignatius, eldest son of the next generation, was also ordained in the Moravian Church and in 1787 became secretary to the Society for the Furtherance of the Gospel... (etc.)
http://www.adb.online.anu.edu.au/biogs/A020077b.htm

Sue