def get_phylogenetic_weight(node):
	"""Calculate the weight at a phylogenetic node.

	Args:
		node (`Node`): The phylogenetic node.
	
	Returns:
		float: (weight of the parent) / (number of siblings + 1).
	
	"""
	if node.parent is None:
		return 1.0
	return 1.0*get_phylogenetic_weight(node.parent)/len(node.parent.children)