Babies start to display more obvious and observable social behaviours, recognise and prefer the company of familiar people, but usually accept cuddles and comfort from any person
Babies start to display anxiety directed towards strangers (stranger anxiety) and anxiety when separated from their attachment figure (separation anxiety)
The person with whom the baby has formed a specific attachment, not necessarily the individual the child spends most time with but the one who offers the most interaction and responds to the baby's 'signals' with the most skill
Schaffer and Emerson's research involved observing 60 babies - 31 boys and 29 girls, from Glasgow and mostly from skilled working-class families, visiting them and their mothers in their own homes every month for the first year and again at 18 months
Schaffer and Emerson asked the mothers questions about the kind of protest their babies showed in seven everyday separations, to measure separation anxiety, and also assessed stranger anxiety
Schaffer and Emerson's stages have practical application in day care, as they inform how to plan for babies' needs during the different stages of attachment