[ladyinthemists]

If a surname ends in a "y", what is the correct way to show plural possession when an "s" is added at the end as in speaking of "the home of the Tenny family"? Would the appostrophe be before or after the "s" when indicating plural ownership? And, when speaking of a group of the Tenny family would it be "the Tennys" or (as someone seriously suggested to me) "the Tennies"? I know that in the case of a given name of a person who's name ends with a "y" possession is shown as "Sandy's" but I am unclear in regards to a surname when it relates to the possession of a family as a whole. Thank you for any assistance you may be able to offer me.