Andrew Leiper is a complete mystery - and appears at this stage to be a solid brick wall.
Known facts are as follows
Note: It is believed that Andrew Leiper is the father of Walter Leiper in name only  and has no biological connection - DNA analysis of Walter's descendants appear to confirm this.
It is suspected that "Brighton" is not actually place of birth, but possibly where Andrew left England from.
It is unknown which year is more likely to be the year of birth - especially since the one date comes from the birth that was registered by a friend, and not by either the mother or father. As such, suggesting that he was older than, or about the same age as his wife, seems logical, and therefore being born sometime around or before 1823 seems likely.
Regarding the 1856 Residence locations: Castlemaine and Maryborough are approximately 48km (30miles) apart by today's roads.
I have not been able to find a death registration for Andrew within searchable Australian Death indexes, using 1856 as the earliest date of death given that the child John Andrew Leiper was born in December of that year, and the knowledge that as at 1859, he was not with his wife. It is unknown if he even died within Australia.
Andrew Leiper was also not with his wife in 1860 when she had to place their child into state care, which is why I strongly suspect that the child Walter born in 1864 has no biological connection to Andrew Leiper.
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