Gaze following in macaques

Chapter 12 endnote 10, from How Emotions are Made: The Secret Life of the Brain by Lisa Feldman Barrett.
Some context is:

A mother macaque may follow her infant’s gaze, but she will not look back and forth from the object to the infant’s face, as if inviting her baby to wonder what is in her mind.

Macaques can follow one another’s gaze to look at something interesting, but tend not to look into the eyes of their infants; in a macaque, a direct stare signals threat. Adults also tend not to use their own gaze to encourage their infants to broaden their affective niche.

See also

• Gaze following in chimps