New to board-some questions regarding 5 year old son and asthma

Hello

I have three lovely boys who are 5, 3 and 16 months. My eldest son, Isaac, has asthma. Actually his history is a little complicated but the long and short of it is that he is now treated for asthma. I guess I am now only fjust full accepting this after years of blaming his respiratory problems on a bad virus which put him onto a ventiator when he was 14 months. But in some ways as he gets older teh asthma itself is coming out more and it is obvious that he does have it.

Isaac is currently on montelukast, inhaled steroids morning and before bed, salbutamol and atrovent.In the past he had a lot of oral steroids, oxygen, nebs, anti-biotics (forever having had chest infections) etc.

So as a Mum coming out of denial (despite having used asthma meds for the last 4 years) I have a few questions.

I always thought that asthma meant wheezing (I have no asthma in my family and no friends with it). Isaac only wheezes really at night when really bad. Otherwise he coghs, he coughs a lot. The night cough is terrible at the moment. Is this quite typical for children with asthma, or are they all different?

Isaac is tiny- he is on teh second centile for weight and 25th for height. His three year old brother is teh same size. I am told that this is unlikely to be due to his problems, is slow growth and asthma something that in your experience can go together?

At what stage do you think it is good to try and properly explain asthma to your child, and is there a good information source, age appropriate to help with this? (Isaac is a worrier so I have always tried to brush over it lightly without scaring him)

Now that ISAAC HAS just started school the fact that virus's hit him a lot harder means that he has already missed quite a bit of school, how do other parents deal with this?

Sorry for all the questions and please don't feel you have to answer them all, any info would be great

A worried Mum!