This can be gastroesophageal reflux disease or GERD (called as reflux also). This can cause cough on laughing or after the food and incidentally; also very commonly known reason for the night sweats. An upper gastrointestinal endoscopy (camera exam) and a barium swallow (x-ray test) would be able to confirm it. The other possibility can be bronchial asthma and an auscultation by a doctor would diagnose it. The treatment of asthma is by bronchodilator medications, nebulizer and inhalers. The GERD is treated by antacids (Maalox, Tums) and acid blockers (Prilosec, Zantac).
Please feel free for your follow up questions.