That's not unusual, as she probably didn't get bred in her first estrus cyle and got bred when she came in a second time in December. Normally our fawns up in this area are born in late May to early June and those does that didn't get bred in late October through November will breed into January sometimes with their fawns not dropping until July. I saw spotted twins one time here in southern Michigan during our late November deer season, so their Mom probably wasn't bred until as late as February or March.