It’s a gray area. The Church doesn’t provide for it, or for EMHCs blessing adults for that matter, and so it really shouldn’t be done. But, rather than make an issue of it, Catholics uncomfortable with receiving such blessings (or with their children receiving such blessings) should strategize where they will sit and from whom they will receive Communion before entering the Communion line. This may mean taking the time to note which seating areas ordinarily are served Communion by a priest or deacon and planning accordingly. If you make a mistake and you or your child are offered a blessing by an EMHC, accept it without comment. To refuse or reject a blessing, either for yourself or for your child, can only cause hurt feelings.