Hi Kerry, sorry I am having a great deal of trouble trying to navigate this website, hopefully this reaches you.
Richard's son Henry (Leonard) was my great grandfather, then John grandfather, then Reginald father. I grew up in Kangaroo Valley (now Lenah Valley) and recall my father's family orchards in Bushy Creek Road before the 1967 fires destroyed them.
Heritage websites suggest that Richard's mother is Sarah Hickmer (later Lusted), born around 1776. Sarah had two other children James Hickmer (born 1792) and John Hickmer (born 1798). Some sites suggest that Sarah's husband Joseph Lusted was the children's father (not sure about this as they married well after the children's births in 1803, but I cannot find any further children for them).
Sarah's parents are nominated as Richard Hickmer (Hickmar) (born about 1742 -1782) and Ann Hickmer (nee Thomas), born 1743-1767 on some sites.
Going back farther, some sites suggest the above Richard Hickmer (born about 1742) is the son of Richard Hickmore, (born around 1720 - 1791) and Elizabeth Hickmore (nee Lassender) (born 1720-1767, married in 1741). Noticeably he the married Elizabeth Hickmore (nee Hermer) in 1769.
The above Richard Hickmore was born to Richard Hickmore (born circa 1690) married Elizabeth Hickmore (nee Mills) (born about 1694).Married 1715. They were also known by Hickmett and Hickmar.
His father is listed once as a Joseph Hickman.
Dates appear to be align mostly to what you would expect. Way too many Richards and Elizabeth's to have too much certainty. Some data I'm not too confident with either.
How have you gone with your search? Gen