It's probably a little bit late for this, but I thought I would extend a public-service announcement related to holiday cards. If you are signing your family's name on the card, do not use an apostrophe. Even if your last name ends in "y." I'm probably preaching to the choir, but this seemed relevent for today.
And now for today's apostrophe catastrophe, submitted by
Alan, a prolific contributor to this blog.

It should just say "The Jonkmans," or "The Jonkmans' House." He says he tried to explain the error to the owner of the store where he found the sign, to no avail.
Thanks, Alan!