How to access a symbol hash key using a variable in Ruby

You want to convert your string to a symbol first:

another_family[somevar.to_sym]

If you want to not have to worry about if your hash is symbol or string, simply convert it to symbolized keys

see: How do I convert a Ruby hash so that all of its keys are symbols?

You can use the Active Support gem to get access to the with_indifferent_access method:

require 'active_support/core_ext/hash/indifferent_access'
> hash = { somekey: 'somevalue' }.with_indifferent_access
 => {"somekey"=>"somevalue"}
> hash[:somekey]
 => "somevalue"
> hash['somekey']
=> "somevalue"

Since your keys are symbols, use symbols as keys.

> hash = { :husband => 'Homer', :wife => 'Marge' }
 => {:husband=>"Homer", :wife=>"Marge"}
> key_variable = :husband
 => :husband
> hash[key_variable]
 => "Homer"