4 YO constant illness

[Shellyxx]

Long story short my 4 yo since she's started school when she was 3 has picked up constant illnesses which I expect however they linger for SO long. Every single time the dr says 'give it 3 days' but they last like 2/3 weeks?

She's diagnosed with asthma but it's like the simple cold which she appears to have no and have had for 2 weeks so far, a red raw throat, and a temp. She looks so pale and so unwell.. I'm sick of her looking like this, it's not fair to her. She's fine In herself at the moment just a little tired and snotty. But she looks so poorly. She has multi vits and the drs did bloods but I'm still concerned as to why so the illnesses always last so long as take over?

Poor little thing. Did the bloods come back okay? What is her diet/weight like?

When they were done ages ago, it came back as low iron, she wa given iron supplements and had an allergic reaction to them but the doc said it was only a tiny bit low anyways so just give a multi vit and some foods with iron it SO I did and they were rechecked and fine.

Her diet she eats a lot of fruit and occasionally some veg. She's quite fussy. And she is classed as overweight too which I'm working on although she doesn't look 'massively overweight' but she is according to the numbers so I'm working on that.

Idk, I see a lot of parents saying the illnesses are so frequent but the other kids never seem to be down with it for as long.