Anak, please go back to your baby's doctor or pediatrician right away, lalo na't may nana na at pabalik-balik pa rin kahit naubos na ang antibiotics, kailangan ninyong malaman kung bakit ganyan. Hindi ko dapat mag-suggest ng gamot dito, pero ang importante talaga ay makita ng doctor kung ano talaga ang nangyayari at maybe kailangan ng iba pang approach. One of my mum friends had something similar and turned out kailangan ng mas detailed check-up lang. Seryoso lang, anak, magmadali, huwag maghintay, especially may nana na. Sending hugs, you're doing the right thing by seeking help!