Hello,
Thanks for posting your query.
It seems that your child is most probably suffering from a respiratory infection causing either nasal obstruction or wheezing both of which can cause noisy breathing aggravated during sleep or recumbent position.
In order to be able to guide you better I would like a detailed history of his illness like,
1. The onset duration and progress of his symptoms .
2. The severity of his fever , cough , any breathing difficulty or fast breathing ?
3. Wether examined by doctor , any tests done and details of any medicines given.
4. Any significant past or family history of medical problems .

As of now I assume your child had a bout of fever last week , followed by cough and now wheezing all of which are suggestive of chest congestion due to respiratory infection.
The best step would be to get your child examined by his pediatrician who may / may not carry out any tests like xray or cbc if needed ( depending on severity) and start appropriate treatment .
The treatment most likely includes a antiinflammatory analgesic like acetaminophen for fever , bronchodilator medication like terbutaline or salbutamol ( inhaled or oral), cough expectorant or mucolytics ( ambroxol ) and decongestants like chlorpheniramine . If the doctor suspects a bacterial infection he might advise a course of antibiotic like Cefixime or azithromycin .
As of now if such treatment is going on then it's advisable to wait and watch for a week to ten days for resolution of symptoms . If symptoms worsen or persist its best to get the child investigated thoroughly .

Hope I have answered your query.
Awaiting your response,
Regards

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