Babies start to display more social and observable behaviour, show a clear preference for being with other humans rather than inanimate objects, recognise and prefer the company of familiar people, but will usually accept cuddles and comfort from any person
Majority of babies display clear signs of attachment towards one particular person, including anxiety during separation and joy upon reunion with the attachment figure
Shortly after forming a specific attachment, babies start to extend this attachment behaviour to multiple other people with whom they regularly spend time, forming secondary attachments
Schaffer and Emerson's research involved 28 babies - 3 boys and 25 girls - from Glasgow, visiting them and their mothers monthly for the first year and again at 18 months
Schaffer and Emerson assessed the babies' attachment by asking the mothers questions about the kind of protest their babies showed in seven everyday separations, and also assessed stranger anxiety
Schaffer and Emerson's stages may not generalise well to other populations, as they only looked at one sample from 1960s working-class Glasgow, and other cultures may have different norms around multiple attachments