For us, having a rigidly consistent routine helped that kinda dovetailed into bedtime. Supper at the same time, baths/teeth brushing at the same time, pajamas at the same time, etc etc.
Maybe you're already doing that, but it helped for us. Every kid is different, so obviously your milage may vary
Cry it out and if that does not work after a few days consult your pediatrician about melatonin.
Oldest did cry it out in a few days and was good. Youngest kept us up for two years until we started melatonin.
Ours said no melatonin til 3 yrs. 18 months seems early, even without that in mind.
Mine are 9 and 11 now so my timeline may be off...
Does it all blend together at some point?
Yes and no specific dates and times do but you still remember all the parts of the journey.
For child 1: he would take 2 hours to get to sleep and then wake up every 45 min, every night. We used the sleep training described in Precious Little Sleep, and in 3 nights he was falling asleep himself and sleeping through the night.
For child 2: same start as child 1. We tried the above, and everything else we could think of. Nothing ever worked. I finally convinced my wife to keep him in our room and he disturbs our sleep every night still; but at least one of us doesnt have to go to the other room and screaming doesn't wake the other child. He's recently turned 5 and promised he will sleep in his own room, so tonight is literally the first night we're trying to get him to sleep on his own. UPDATE: success!!
My advice is: good luck. Try whatever sounds good to you (some people find it completely unacceptable to let a child "cry it out"), but ultimately, parents aren't the ones in charge and kids do what they feel like.
My son would only sleep if he was being held, as soon as he got horizontal for bed he'd be wide awake...It was a tough time.
We had 3 kids at that time ages about 7, 3, 1. And my eldest struggled to sleep also.
What solved it for us was putting two queen mattresses side by aide on the floor and just having the kids all sleep with us.
I understand the Western World often sees this aa a negative solution, but its common in other cultures for kids to sleep in the room as the parents.
The kids felt safe, and parents could doze a bit if the kids were awake, but at least not crying.
Once they got older we moved them back to their bedrooms.
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