Santa's reindeers were resting up for the holiday, so Kris Kringle arrived at the MGH via MedFlight helicopter Dec. 21 for a pre-Christmas visit. Santa — known any other day as Mike Lessard, MedFlight Equipment Retrieval operator and Dedham Fire Department Lieutenant — was accompanied by a pilot and two elves who double as nurses for their fourth aerial arrival to the hospital. Santa and his flight crew visited pediatric patients, including McKenna Lappin, at right, on Ellison 17 and 18. They handed out helicopter pens, calendars and polar bear stuffed animals. Thanks to MedFlight’s quick transport, the jolly ol’ man in the red suit has plenty of time to make it back to the North Pole and ready his sleigh for the big night.