My Daughter Is Nine Month Old Suffering From Severe Cold

My daughter is nine month old suffering from severe cold n congested nose. Ocassional cough which lasts for about 6 to 8 minutes.Can i give her omnacortil along with nebulization(3%NS). Her chest is full of phlegm n has congested nose with difficulty in breathing. Does omnacortil helps in expectorating the phlegm. Or suggest me wat to do to expectorate her phlegm. She is finding it very difficult to breathe n expectorate the phlegm which leaves her very cranky.