this is possibly
halitosis due to infection of para nanal,and nasal sinuses.
TRY XYLOMETHAZONE NASAL SPRAY(
OTRIVIN)
ANTIBIOTICS LIKE AMOXYCYLLIN AND ANTIALLERGIC LIKE LEVOCETRAZINE SHOULD HELP.A SHORT COURSE TREATMENT GENERALLY IS SUFFICIENT.
ALSO TELL WEATHER SHE HAS RECURRENT SORE THROATS ?
IF PROBLEM PERSIST GET AND XRAY OF NASAL AND
PARANASAL SINUSES DONE