I was reading an interesting article yesterday about helping camp counselors think about the reasons a child behaved in an unacceptable way before they dealt with the problem & how the change in thinking actually dramatically reduced the problems that were occurring. The concept came from understanding and working with research in neurobiology.
So my first comment would be rather than look at what you need, try to look at what your DD is telling you she is needing & look at why she might be needing that contact & why it is causing her to struggle at bedtime in terms of what happens in the day etc.
In the later weeks of pregnancy it is harder to do many things & so the older child starts to notice they are getting less of the things they have seen as important, so the having Mum at bedtime is something she can control with crying (& I don't mean it is her being manipulative) because she can't control other things to have her needs met. Added to which she is on the cusp of the peak time for Separation Anxiety so the trust relationship between you is vital at this time, from a brain wiring point she is right at the most important time for establishing her 'primary connection' & so there is a degree of 'abandonment' feeling when she is left alone in her bedroom - from an evolutionary point of view it's only been the last 100+ years & only in Western society that babies & toddlers are left to sleep in their own rooms, so in many ways it is about a fine balancing act of what is what we do in western society & what is normal from an evolutionary perspective.
Some of the things that I'd be looking at to try & help her settle better is - does she do the same thing if other's put her to bed, does she do better if you have a longer wind down at bed time (its easy to want to rush when you are tired & pregnant) How many nights did she sleep in the bed with you & how gradually did you transition from that big change back to her own room. Did at any time she cry for a longish (like 5mins) time without you going to comfort her which could have caused such a traumatic response for her to vomit. The reason I ask that is that I always slept in the bed (not always my bed) with my boys when they were sick & while there was a transition with them going back to their own there was never a huge reaction to it & they got back to where we were within a week using a gradual process.
With the projectile vomitting I would probably stay in the room and do more of a gradual withdrawal approach (as well as perhaps seeing the dr as vomitting that quickly seems odd to me). Was it a tummy bug she had?
Yes the vomitting so quickly is of concern, maybe there is a medical factor there.
Anyway if it was me, I'd be planning on investing a good hour or more on bedtime each night, starting with a longer wind-down time (with a plan to gradually cut back before the baby is due) & then stay with her until she is asleep for at least 10mins stroking her leg on off, having a plan that over time you decrease the contact every couple of days... so first day you sit & have a hand on her until she is sound asleep, 3 days later you take the hand off for periods of time & then move to just being there. In terms of the demands of juggling 2 children, well I found if I had to do both children's bedtime on my own, what worked best was to feed DS2 in the dark while I sat with DS1 until he fell asleep. One of the challenges of parenting is finding the balance between our own needs & those of the children & I've found that often the solution is clearer when I take a step away from what I might want & look at what it is my child is showing they need by what is happening, I'm thinking she is just needing more time with you to be able to relax & fall asleep which is really an age thing more than a product of being sick.
