So Why Do We Say Rabbit, Rabbit, Rabbit...

on the first day of each month?  I know that my siblings do this and we were taught at an early age it had to do with bringing good luck.  Herein, is a posting from Wikipedia...go figure:

The exact origin of the superstition is unknown, though it was recorded in Notes and Queries as being said by children in 1909:

"My two daughters are in the habit of saying 'Rabbits!' on the first day of each month. The word must be spoken aloud, and be the first word said in the month. It brings luck for that month. Other children, I find, use the same formula."

In response to this note another contributor said that his daughter believed that the outcome would be a present, and that the word must be spoken up the chimney to be most effective; another pointed out that the word rabbit was often used in expletives, and suggested that the superstition may be a survival of the ancient belief in swearing as a means of avoiding evil.

It appeared in a work of fiction in 1922:

"Why," the man in the brown hat laughed at him, "I thought everybody knew 'Rabbit, rabbit, rabbit.' If you say 'Rabbit, rabbit, rabbit'—three times, just like that—first thing in the morning on the first of the month, even before you say your prayers, you'll get a present before the end of the month."

Today it has spread to many English-speaking countries and in the United States the tradition is common in New England, in particular in Massachusetts, New Hampshire and Vermont, although, like all folklore, determining its exact area of distribution is difficult. The superstition may be related to the broader belief in the rabbit or hare being a "lucky" animal, as exhibited in the practice of carrying a rabbit's foot for luck.

During the mid-1990's U.S. children's cable channel Nickeloden helped popularize the superstition in the United States as part of its "Nick Days", where during commercial breaks it would show an ad about the significance of the current date, whether it be an actual holiday, a largely-uncelebrated unofficial holiday, or a made-up day if nothing else is going on that specific day. (The latter would be identified as a "Nickelodeon holiday".) Nickelodeon would promote the last day of each month as "Rabbit Rabbit Day" and to remind kids to say it the next day, unless the last day of that specific month was an actual holiday, such as Halloween and New Year's Eve.  This practice stopped by the late 1990s.

Rabbits have not always been thought of as lucky, however. In the 19th century, for example, fishermen would not say the word while at sea, and in South Devon to see a white rabbit in one's village when a person was very ill was regarded as a sure sign that the person would die.