What kind of filter I Need...????

Currently I have 60d + 50 f1.4 + 430 exII + hoya UV filter and interesting for people photograph     (about 90 % +) especially my family. So far I am glad to the results, however sometimes I found skin affected (sparkling) by flash (or may be by existing light) even while I bounced may be because some of family have a little oily skin. Can this rectify by filter???? what kind???

Thank's to any response

Regards

Dedirg