AP Photo/Peter Morrison
A man and a baby boy watch the the St. Patrick's Day celebrations in Belfast, Northern Ireland, Thursday, March, 17, 2011.
AP Photo/Peter Morrison
A girl with shamrock tights joins in the St. Patrick's Day celebrations in Belfast, Northern Ireland, Thursday, March, 17, 2011.
AP Photo/The Ledger Independent, Terry Prather
Jim Tierney, left, and the Rev. Ivan Kalamuzi lead a St. Patrick's Day parade along the downtown streets, in Maysville, Ky., on Thursday, March 17, 2011.
AP Photo
Emma Shelley, 6, of Penbrook Pines, Fl., sits on a side street waiting for her sister to march up Fifth Ave during the St. Patrick's Day parade, Thursday, March 17, 2011, in New York.
AP/Photo
President Barack Obama during his meeting with Irish Prime Minister Enda Kenny in the Oval Office of the White House, in Washington, Thursday, March, 17, 2011.
AP Photo/Tina Fineberg
Jack O'Rourke, 4, left, and his twin sister Claire O'Rourke share a laugh as Mia Hayes, 4, right, holds an Irish flag as they watch the St. Patrick's Day Parade make it's way up New York's Fifth Avenue, Thursday, March 17, 2011.
AP Photo/The Montana Standard, Lisa Kunkel
Three-year-old twins Danny, left, and Robert McCarthy look out the window of a classic car during the annual St. Patrick's Day parade, in Uptown Butte, Mont., Thursday, March 17, 2011.
AP Photo
In this combo of photos, baseball fans celebrate by wearing a variety of green caps and hats on St. Patrick's Day during a spring training baseball game between the Boston Red Sox and New York Mets, in Fort Myers, Fla., Thursday, March 17, 2011.
AP Photo
Danny Doherty, left, and Jim Conroy, both from Dumbarton, Scotland, watch the marchers make their way up Fifth Ave during the St. Patrick's Day parade, Thursday, March 17, 2011, in New York.
LEON NEAL/AFP/Getty Images
A couple celebrating St. Patrick's Day, smile during the Cheltenham Festival, in Gloucestershire, central England, on March 17, 2011.
LEON NEAL/AFP/Getty Images
A spectator, wearing a shamrock on his hat, is seen during the Cheltenham Festival, in Gloucestershire, central England, on March 17, 2011.
LEON NEAL/AFP/Getty Images
A police officer gets into the spirit of St. Patrick's Day during the Cheltenham Festival, in Gloucestershire, central England, on March 17, 2011.
CARL COURT/AFP/Getty Images
A girl, wearing a hat shaped like a shamrock, smiles during the St. Patrick's Day parade through central London on March 13, 2011.
CARL COURT/AFP/Getty Images
People, bearing the colors of Ireland, smile during the St. Patrick's Day parade through central London on March 13, 2011.
AP Photo/Worcester Telegram & Gazette, Paul Kapteyn
Cynthia Tanzi, of Lincoln, R.I., talks with friends before the start of the Celtic 5K Road Race on Park Avenue in Worcester, Mass., on March 13, 2011. The race preceded the St. Patrick's Day parade.
Jonathan Daniel/Getty Images
Members of the Chicago Blackhawks "Ice Crew" wear green outfits for St. Patrick's Day during a game between the Blackhawks and the San Jose Sharks at the United Center on March 14, 2011, in Chicago. The Blackhawks defeated the Sharks, 6-3.
CARL COURT/AFP/Getty Images
A man dressed as a Leprechaun takes part in the St. Patrick's Day parade in central London on March 13, 2011.
AP Photo/Paul Beaty
The Chicago River is dyed green Saturday, March 12, 2011, ahead of the St. Patrick's Day parade in Chicago.
AP Photo/Paul Beaty
A kayaker paddles on the Chicago River after the Chicago River was dyed green Saturday, March 12, 2011, ahead of the St. Patrick's Day parade in Chicago.
ARL COURT/AFP/Getty Images
People, bearing the colors of Ireland, smile during the St. Patrick's Day parade through central London on March 13, 2011.
AP Photo/Kitsap Sun, Larry Steagall
Art Brown from Gig Harbor, a piper for the Tacoma Scots Bagpipe Band, plays in the rain at the Bremerton Main Stream Association 20th annual St. Patrick's Parade, March 12, 2011 in Bremerton, Wash.
AP Photo/Paul Beaty
Chicago Mayor Richard M. Daley waves during the St. Patrick's Day parade in Chicago, Saturday, Mar. 12, 2011.
CARL COURT/AFP/Getty Images
A man dressed as Saint Patrick entertains the crowds during the St Patrick's Day parade through central London on March 13, 2011.
AP Photo/Worcester Telegram & Gazette, Paul Kapteyn
From the left, Nora Murray, 6, and Maggie Dowd, 7, both of Worcester, Mass. hold hands as they march with classmates from the McInerney School of Irish Step Dance during the annual St. Patrick's Day Parade in Worcester, March 13, 2011.