RSV (first time dealing with it, need help)

Good morning ladies I haven’t been on here a lot lately because both my kids have been really sick my seven-month-old contacted RSV which was scary and itself I don’t think I slept for 48 hours because the sleep apnea was so bad, it started last Tuesday and came on with a vengeance. This weekend that just passed he seem to of been improving Just had that wet lingering cough, he was never back to “normal” just not as bad but last night it was like he regressed right back, full stuffy nose can’t drink from congestion wet cough multiple time in a 15 min stretch and sneezing. So my question is this is it possible that he’s contacted another virus which we haven’t been anywhere because they’ve been so sick or does RSV symptoms come back before officially leaving? I’ve never dealt with RSV before so this is all new extremely scary though.