any advise

i have a ds who is 4.5 who has asthma, however my youngest is 8 months old and developed a cough and a wheeze beginning of the month, he was 1st given anti biotics then salbutamol which we was told to use when he was wheezing, anyhow we took him bk to the gp 2 weeks ago who confirmed he had bronchiltis and could now make him wheezy everytime he gets ill, hes had the on going cough now just when he sleeps non stop, but a few days ago started with another horrendous cough and wheezing again and having terrible coughing fist which is making him sick.

when my eldest son does excersie for eg he has coguhing fits where he struggles to breathe so give him his salbutamol, would the salbutamol would with my youngest whe hes having coughing fits? weve been giving it when hes wheezy which helps but obv can be coughing for ages.

as my eldest has asthma weve been told my youngest may get it to and bronchiltiis is what triggered his asthma off when he got it at 6 months old.