Assertion: otter's cub | /r/CapableOf | open their eyes
Facets:
value: at a month
type: TEMPORAL
Source sentences:
text: Cubs are kept in dens for the first few weeks, begin to open their eyes at a month old, and by 9-10 months are independent hunters.
text: The cubs open their eyes after one month and by the second month they start leaving their nest.