DD1(4) sleep refusal and waking DD1(2)

[YBR]

DD4 is a terror most evenings with bed time. I'm frequently having to count her (if you dont get into/out of the bath/put pyjamas on/brush your teeth in 5/10 then ...)
Then she keeps putting her light back on and we remove the bulb.
Last night she was still up and shouting at 8:45pm, and I was loosing my rag and very cross mummy. She still didn't get the point.
Worst of all she was waking DD1 who needs more sleep and is generally a delight at bed time (other moments however ...).

I'm at a loss what to do as I don't have the imagination to come up with appropriate consequences/discipline. What has anyone else tried and has it helped/worked?

My typing/proofreading is dire - must be sleep loss.
DD1, aged 4 is waking DD2 aged 2.

Keeping an eye on your post and this will be me in 6m time! Do they share a room? Mine will have to and although my son 3 is generally good at going to bed, I'm wondering how my daughter will be and how it will work them having to share.