query methods for parents

[mices]

I'm trying to do something like the code shown below but rails returns undefined method name for nil
% if @person.parents %>
<% if @person.mother %>

Mother:
<%= @person.mother.name %>

<% end %>

<% if @person.father %>
   	<p>
	  <strong>Father:</strong>
	  <%= @person.father.name %>
	</p>
<% end %>  

<% end %>

[masciugo]

it seems that @person does not have a father