Anyone’s child had a cough that won’t budge?

[Eden55]

Looking to see if anyone has experience similar.
4 year old has had a wet, chesty cough for about 12 weeks. Assumed viral as not unwell no fever but since it’s lasted so long I finally made a GP appointment they advised chest was clear and to try a nasal spray to try and stop the runny nose and the mucus from nose causing the cough for at least 2 weeks.
Advised tonsils were a bit swollen but not touching, lymph nodes fine.
Only other things in can think of is she sweats in her sleep, not drenched but enough to wet pillow, snores in sleep, maybe a bit pale but fair complexion anyway but otherwise well and developing well.
anyone else’s child had a chesty cough that just won’t budge? And ever find the cause?

The combination of cough and night sweats is a bit worrying - that's one of the signs of TB, although that's unlikely unless you live in a part of the UK with high rates, or have travelled abroad. I don't think a stethoscope examination can rule TB out. Any other symptoms like weight loss, tiredness?

Other options are pertussis even if vaccinated (they might not whoop if they have been vaccinated) or Mycoplasma pneumoniae. Both can cause Hundred Day Cough. I think I had pertussis in January (thanks toddler!) and the cough was unrelenting for a whole month.

@OtterMummy2024 no abroad holidays and not in a high TB area so assume unlikely, the night sweats aren’t drenching her but enough to wet her hair/ pillow sometimes.
Dr certainly didn’t mention TB.
She is also fully vaccinated but I’m not discounting any of these options as the cough is relentless, it’s tiring for her but not to the point she’s exhausted, still acting her usual self, no weight loss.