Eight year old vomited in bed after being asleep. Didnt complai. Of any issues before bed, ate normal meals, played outside before bed. Has had nasal congestion for 2-3weeks. Also vomited last week early in morning, then remainder of day was fine-running around, eating, etc. Is is post nasal drip/drainage causing him to vomit? Hes been coughing A LOT at nite lately and has started to during the day for last 2 days.