Nearly 8MO sleep getting worse - any ideas welcome?

[EMS23]

My 8mo DD was a great sleeper from about 4 months old onwards.. would generally sleep 7pm to 5am, occasionally doing the full 7-7.

At 6MO I went back to work full time and she got chicken pox, followed by teething so cue 4 weeks of awful sleep but that was ok, I understood why.
But since then she's never gone back to sleeping that well.

The last couple of weeks she has been going down at 7pm and waking at 2am for an hour of rocking and cuddling, then 4am generally till I give up and give her a bottle at 5am ish and then she goes back to bed till 6 - 7am.

She always had a dummy but never at night, however with the chicken pox and teething, we gave her the dummy at night and as we were suffering with lack of sleep and it seemed to settle her, we let her have it in her cot.

The other issue which I've wondered about is food... she started weaning at about 5 months and quickly progressed onto 3 meals a day, plus 4 bottles (early morning, mid morning, mid afternoon and bedtime). But she's not a great eater, she's only little (15lbs ish) and just doesn't eat much in volume terms, compared to friends babies her age.

So, any ideas as to what might be causing this and how to get back our good little sleeper?
The last two nights I've given her a bottle at the 2am wake up, which she has taken quite well but she's still then woken up at 5am.

If it's hunger, any ideas how I can get her to eat more solids or suggestions on what solids will fill her up more efficiently? I give her meat, fish or lentils with veg for dinner but should I maybe incorporate more carbs?
Or maybe more proteins at lunch? Or should I try to squeeze in another bottle, although I'm not sure when I could as all we seem to be doing right now is bottle, food, sleep!

I should also mention she naps quite well - generally a morning nap of about 1.5 hours and an afternoon nap of an hour.

[Fuzzled]

Hi, didn't want your message to go unanswered, but am no expert!
My 9mo DS also had a sleep glitch at about 8 months old - apparently there is a 9 month sleep regression (due to learning new motor skills/teething etc) and I definitely think he hit this a bit earlier. If it's any consolation, he is now starting to sleep through again (although not past week due to tummy bug).
We also found that DS was getting wind which was disturbing him, so we swapped his main evening meal to lunchtime and he gets more finger food type stuff at dinner time instead - maybe same for yours?
In short, I have no clue - there are lots of reasons, but sadly no manual!