I have researched this and think I might know the cause. Just wondering if anyone else experienced something similar.
DS 2.7 has had a run of really bad colds. He often wakes in the night coughing and blocked up. Been to docs cos of this. He listened to his chest and ruled out chest infection. And said prob not asthma. He said oxygen levels fine and no wheezing. Also he runs around fine during the day without coughing or wheezing.
His colds finally got better, but his breathing is still laboured at night. And his chest sinks in as he try's to breathe. As soon as he wakes this stops. But he seems very tired like he is not getting a good sleep.
I am thinking he may have large or inflamed adenoids, from all the colds. Which are obstructing his breathing through his nose. Other possibility is asthma, but i have a feeling its more to do with his nose being blocked. Going to docs tomorrow to hopefully get antibiotics or referral to ent specialist.
Trying to be armed with as much research myself first as need to get this sorted.