Roderick GOLLAN was born in Ross-Shire Scotland ~1819, arrived in Victoria ~1839 and died in 1898 aged 78 years (Victorian death certificate #8537/1898, informant son-in-law John Storie, states he was 78 years at the time of his death, and had been 59 years in Victoria). His death certificate names his parents as George GOLLAN, bootmaker and Mary Gollan formerly CHISHOLM.
Roderick married Jane LITTLE, daughter of James LITTLE and Jane BOYD, on 27 Jun 1848 (Victorian marriage certificate). They had six children (1849-1862, Victorian BDM index).
Jane LITTLE is also the sister of James LITTLE who married Jamesina Paxton GOLLAN (I'm not yet sure how she is related to Roderick GOLLAN above, if at all).
Roderick and Jane's son George GOLLAN married Sarah WILKINSON, the daughter of Henry WILKINSON and Sarah FLEMING.
Their daughter Hannah married Samuel FLEMING, the son of Samuel FLEMING and Margaret BROWN (the parents of Sarah FLEMING above).
As yet I have not found Roderick on any passenger list, though as his death certificate states 59 years in Victoria it might be assumed that he arrived from Scotland ~1839.
Roderick's death certificate names his parents as George Gollan, bootmaker and Mary Chisholm, and states he was born in Rosshire, Scotland (informant John Storie, son-in-law). However, a baptism record for "Roderick bap 16 Aug 1819 son of George Gollan, shoemaker, Conon Bridge and Janet Shearer, his wife" suggests that Mary Chisholm was not in fact Roderick's mother.
Jackie Garvin has researched Gollans from Conon Bridge, near Inverness, finding a Roderick Gollan and Mary Chisholm with a child George Gollan, shoemaker, who is the right age to have been Roderick's father. This makes Mary Chisholm Roderick's grandmother. A death certificate sourced from Scotland's People for George Gollan died 1870 Conon Village, married to Isabella Innes, names his parents as Roderick Gollan, cooper, and Mary Gollan M N Chisholm, both deceased.
Indeed, George Gollan can be found in the 1861 Scottish census aged 72 living in Conon Bridge with wife Isabella age 51 (Isabella Innes, married in 1834). Given George's age (he was b ~1789), it can be concluded that Isabella is George's second wife, and that he had children from both marriages, including Roderick ~1819.
I believe Mary Chisholm is incorrectly recorded as Roderick's mother in his death certificate (1898). If Janet Shearer died (or left) ~1830-1834, Roderick's grandmother Mary Chisholm may have been a significant figure for 10-14yo Roderick. His family may have known that Isabella was his stepmother rather than his mother, hence the use of another remembered name.
I have sketched out these relationships in the 'Family Gollan - Families Little & Boyd' tree below.