This morning our 3 1/2 year old was overheard singing his own version of Old MacDonald to brawny baby - the new verses sound like this:
Old MacDonald had a farm, EIEIO.
And on that farm he had a taxi, EIEIO. With a beep beep here, and a beep beep there, here a beep there a beep, everywhere a beep beep.
Old Mac Donald had a farm, EIEIO.
And on that farm he had a fire truck, EIEIO. With a weeooo weeooo here and a weeoo weeooo there....
... you get the picture.