Among the movies directed by Wolfgang Reitherman, how many of them were released in December?
Wolfgang Reitherman refers to director = 'Wolfgang Reitherman'; released in December refers to (release_date, instr(release_date, '-') + 1, 3) = 'Dec';
SELECT COUNT(movie_title) FROM characters AS T1 INNER JOIN director AS T2 ON T1.movie_title = T2.name WHERE SUBSTR(release_date, INSTR(release_date, '-') + 1, 3) = 'Dec' AND T2.director = 'Wolfgang Reitherman'