"Tree of Hope", remembering those affected by Past Adoption Practices

The "Tree of Hope", by artist Kristina Nichols, is located in the upper section of the Hobart Royal Botanical Gardens. 
The memorial, which was installed in October 2013, is dedicated to all those affected by Tasmania's practices of forced adoption, where (unmarried) parents were made to give up a child for adoption. This happened in Tasmania until the 1980s.
A small plaque includes a quote from the formal apology given by the Tasmanian Premier Lara Giddens on 18 October 2012: "To those people who have held their pain close for so many years, who have lived their lives under a shadow of secrecy, shame, anger, guilt and deeply held trauma and loss, we offer you our unreserved and sincerest apologies." 
The memorial was funded by a $10,000 grant from the Premier's discretionary fund.
 Made of corten steel and polycarbonate, the human-size sculpture sits in a woodland area not far from the main entrance. The steel is cut to form a silhouette, and is patterned by the effects of weathering. In the spaces created by the silhouette design clear polycarbonate sheets catch dew of water, at times looking like tears. In certain lights, this clear plastic reflects the viewer.
The Botanical Gardens hosts a number of other permanent public sculptures, as well as other temporary art installations from time to time. This conext may help increase curiosity about the memorial. Casual walkers regularly stop to look at and to read the accompanying plaque. 
The "Tree of Hope" is surrounded by wooden bench seating for visitors who would like to spend some time reflecting, and the woodland setting certainly creates a tranquil space. However, it is dwarfed by some massive specimen of living trees. It is hard to know whether this was a deliberate choice, and reflects the idea that hope is a small and fragile plant, or whether it is simply an outcome of the relatively low level of funding given to this project. 

Stolen Generations Memorial, Mt Annan Botanical Gardens

The Stolen Generations Memorial in the Mt Annan Botanical Gardens, near Campbelltown on the outskirts of Sydney, acknowledges the experiences of Aboriginal people separated from their families because of racist government policies. The memorial came about because of the advocacy of Stolen Generations people, in particular Carol Kendall, an Aboriginal woman who was adopted by a non-Aboriginal family and who became a respected leader in the fight for recognition of this history. The memorial was developed as a partnership project of the Botanical Gardens Trust, Link-Up NSW and the NSW Stolen Generations Committee.
The memorial takes the form of a circular journey along a wheelchair-accessible boardwalk through the bush, leading to a central clearing with a sculpture, water feature and bench. The path then leads back out to the main road, not far from a picnic area. For visitors for whom the journey is particularly personal, this means they can walk the path alone and return to their companions when they are ready. The boardwalk was constructed by local Gandangarra people as part of a skills development program.
The journey is punctuated by plaques containing quotes from stolen children, some of which are contained in the Human Rights and Equal Opportunities Commission's 1997 Bringing Them Home Report. From the boardwalk, concrete slabs imprinted with a child’s footprints lead to the sculpture, with more concrete slabs, this time showing adult footprints, leading away.

The central sculpture was carved on site by Badger Bates, a Paakantji man from another part of NSW. One side, facing the entry from the boardwalk, is a relief sculpture depicting a nuclear family of a man, woman, baby and small child in a circular composition, framed by gum branches above. Between the man and boy on one side and the woman and baby on the other is a niche into which two small bowls are nested. Visitors are invited to fill the bowls with water from the small pond at the foot of the sculpture and pour them out as a symbol of their tears.
The ‘back’ of the sculpture is more abstract, and interpretive signage at the site explains that it represents the anger and sadness of the Ngatyi or Rainbow Serpent, “over the hurt done to his people who were taken away from their Country.” The artist has said it is carved as a ‘gift’ to the Stolen Generations. While the circular journey of the memorial offers a healing ritual for Stolen Generations people, the interpretive signage is directed at a 'non-stolen' public, who are asked to take part in the ritual pouring out of tears and to put themselves 'in the place' of the families who were, and often continue to be, separated.
Mt Annan was a traditional meeting place for clans of the Dharawal people before being taken over as farm lands by Europeans. In the mid 1980s, the land was designated as a botanical gardens by the NSW Government as a Bicentennial project; that is, as a part of the celebration of the arrival of the 'first fleet' in Sydney Cove, an event remembered as ‘invasion’ by many Aboriginal and non-Aboriginal Australians, as ‘settlement’ by others. The memorial is constructed in an area that retained some of the native bushland and has been extensively replanted.

Questions:

Why did the artist choose to represent a 'nuclear' family of parents and two children in this memorial, when this is usually understood as a traditional Aboriginal understanding of family?