As long as we're celebrating holidays this week, let's do this one. According to one expert resource on holidays:
Origin of International Talk Like a Pirate Day:
"John Baur and Mark Summers created the concept of International Talk Like a Pirate Day on June 6, 1995. While playing racquetball, they began to talk to each other in Pirate-speak". After leaving the court, they decided that there was a need to create this day. After much thought, Mark Summers selected September 19th as the date. This was his wife's birthday. So, he thought it would be an easy date to remember. And so, International Talk Like a Pirate Day was born."
Our family has enjoyed this over the years for several reasons, not the least of which is this:
So, go celebrate. Here is even an official website with all kinds of fun (disclaimer: I haven't been through the whole site, so I don't vouch for it's family friendliness in all areas!)