New number

My younger boys have come up with a new number: octeen.  They burst into giggles whenever they say it, they love to count to it (it can come after any number).  If they are counting on their fingers and get to octeen, they use their sign for it: the "ok" sign.  And, most recently, they have started to call other people octeen.  My latest example is when we were at Ace getting some stain for our picnic bench.  An older-than-middle-age worker helped mix up the stain since they didn't have any of the right color on hand.  As he was walking with me to the check out, the boys kept calling in a loud voice, "Thank you Mr. Octeen!  Good bye Mr. Octeen!"   After explaining to the worker that it was just a made-up number, he replied, "Does that mean I am old???"  I wasn't exactly sure how to answer that...