coughing no sleep.... help

[Minirocky]

So here goes.... Dd2 is 17 months always been a terrible sleeper. Hard to settle, very light sleeper, up every few hours for about an hour or more then up early too. But recently it's got even worse!
She had reflux and cmpa. Now reflux has cleared but still cmpa. molars have finally come through and we thought things might settle down but no!
Over past month she's had double ear infections tonsillitis conjunctivitis and now a severe cough. Back to the docs today.
I feel she's had a bad run of things but also because she's such a terrible sleeper she's not fully recovered from anything. My nan used to say "when you're sleeping you're healing".
Any wise words or advice about how I can help my amazing dd2 (and also get some sleep myself).
Any ideas for long term improvement to our sleep, can't even flush the logo for fear it will wake her.

For the cough, our doctor used cough syrup even though I believe it is not that common any more.
DS is asthmatic so we use a dehumidifier at night.
Also a nasal spray. To clear out the mucus. Head up at an angle for the post nasal drip.
And finally some Piriton if needed.
DS can vomit with his coughing so we usually do all of the above if we think a bad night is in the offing.

Thanks for the reply, is Piriton I case of hay fever etc or for cough?

Also gonna get a dehumidifier today!

Try putting Vicks junior on the soles of the feet with some socks on top.

We put vapour rub on feet too it's an absolute lifesaver. Two of my DC were given blue inhalers as their night coughs were so bad when they were little but we haven't had to use them since we started doing this.