As families gather round for the winter holidays, some faces may be more familiar than others.
A recent study shows that the amount of social interaction between extended family members depends on whether people are related through their mother or father.
Thomas Pollet and colleagues at Newcastle University and the University of Antwerp, Belgium, investigated how far maternal grandparents and paternal grandparents will go to maintain face-to-face contact with their grandchildren. They found that maternal grandparents were willing to travel further in order to sustain frequent (daily or a few times a week) contact with their grandchildren than paternal grandparents.