If she's over 3 I would use firm boundaries and rapid return, not gradual withdrawal.
Basically just set The Rules, accept no deviations from The Rules and the moment The Rules are broken you get to child as quickly as possible and return to bed.
An example of The Rules would be a mantra like:
"It's sleep time now. You lie down quietly in bed at bedtime. Nan night".
That covers everything.
Any time she gets out of bed, for any reason, return to bed and say the mantra.
Any time she makes a noise, go to get straight away, say mantra, leave.
Any time she's sitting up in bed, say mantra and lie down.
Be mega firm and very strict. Be absolutely certain that under no circumstances at any time during the day or night will she ever be able to deviate from The Rules.
Shes going to protest against this, of course. But you are the grown ups. She needs you to set the boundaries, for her own well being.