Thanks ladies. Since posting we've had some huge improvement! She now sleeps (give or take an hour) 8pm-8am and day sleeps have become much easier aswell. We often get at least 1 nap, sometimes 2.

As you said MadB, it's been a time of transition so we really just had to find our groove. Now that it's improved I'm back to feeling happy and confident in my choice to follow her lead, but I've definitely realised that sometimes I need to take charge and it's just a matter of finding the right balance. So now if she looks tired we try to lay down for some quiet time. I'm focussed on just chilling out and relaxing, rather than sleeping. Sometimes she naps, sometimes she doesnt but either way she's had some time to wind down. I also realised that part of the problem was that I was letting nap too late. So now, if we hit 4pm and she hasn't napped, I keep her awake and will wake her by 5pm at the latest if she does have an afternoon nap. That really has helped immensely. In fact, she currently curled up next to me fast asleep and it's not even 7pm! Our next challenge is trying to get her to fall asleep in her own bed. I've taken the side off the cot to make it a toddler bed so we're starting by just trying to resettle her there when she wakes but bringing her back to bed if it doesn't work. It's slow going but there's been definite progress and I'm feeling much less anxious about what will happen when the baby arrives