As part of monitoring a population of Canada Geese (Branta canadensis maxima) in southern Quebec, two siblings hatched in the same nest in 2008 were later observed breeding together. The geese were first seen as a pair in spring 2011, and we found their nest the following year 437 m from their natal nest site. The sibling pair had lower hatching success than other pairs of the same age cohort. To our knowledge, this is the first report of sibling pairing in the wild for a goose species. Adoption is common in geese, and siblings reared in different family groups may be unfamiliar to one another, which may be the case for the observed sibling pair. Since geese are perennial monogamous birds, full siblings are produced each year, providing further possibility for inbreeding, but we found no pairing among siblings of different ages. Natal dispersal was more important for males and this could contribute, with kin recognition, to inbreeding avoidance.