If they are obviously tired, but fighting to stay awake, a short trip in the car usually works in 5-10 minutes. I had a rough bitumen road route all mapped out until it was resurfaced.
I’ve heard the washer on spin cycle can work, but that is probably for younger ages who can’t climb out of a bassinet.
The push to stay awake usually comes from having other people over or some high interest event happening. I black out as many windows as possible and turn off all lights. You can try the same music, prior to bedtime, as a sleep-cue, like a Riff-Raff etc. Try playing a technical monotone podcast or DIY-vid audio, might work.
Sleeping with mum or dad’s worn shirts can help, providing a comforting scent etc.
When lying down in the same room, playing a game of “I’m going to get to sleep first” can often start things off on the road to sleepytown.
Good luck zzzz (c:
I have heard from someone else that it can become an addictive sleep primer.
The other tip I forgot, is that they need to be full of food. If they are very tired/irritable and not going down, offer their 3 favourite foods + some milk. After eating their fill, this should trigger a whole bunch of sleepiness.