A psychologist called Mary Ainsworth (1913–1999) devised the Strange Situation Test but the test is closely linked to the theory of attachment. Attachment theory has become very well known in psychology and is closely associated with the work of John Bowlby (1907–1990), who carried out work on attachment in the 1940s and 50s.
Recent research has shown that not only can babies form multiple attachments but that they are often better able to form relationships in the future if they form more than one primary attachment (David, 2004). These primary attachments do not have to be with the child’s parents. Sometimes children form a primary attachment with a close relative, such as a grandparent, or a parent figure, such as a long-term foster carer. Remember in the case study family that baby Mali was closer to her grandmother Ceri who looked after her while her mother Siân was working.