Ideas to get 21 month old to sleep through the night

[Gablexy]

Any ideas on getting a 21 month old to stay asleep? She goes to bed fairly easily around 7pm. Wakes up about 4 times a night at the moment, much improved on previous months but still frustrating. The first couple of times I can usually soothe her back to sleep without taking her out of her cot, but beyond midnight she stands up, reaches out crying, refuses to lie down and I end up picking her up and taking her to my bed so she doesn’t wake her older brother (they share a room, no third bedroom). Once in my bed she usually sleeps for a bit (taking up most of the space of course!) but invariably wakes up before 5am, thrashing around, chatting away wanting to get up.

She’s pretty chirpy during the day; I don’t know how she’s so cheerful on such disrupted sleep as I’m certainly not! She usually has one nap of about 1.5 hours after lunch, sometimes before. She eats well and has a bit of milk before bed so I don’t think she’s waking due to hunger. She gets lots of fresh air and exercise so whhhhy doesn’t she sleep properly and what can I try to improve things? Thanks for any ideas.

I feel your pain. Since Xmas our DD was sleeping right through. For whatever reason, she started to wake in the night. Just once. But when she wakes, its really hard to get her back down without picking her up and letting her drift off in your lap.
We then did get about 3 weeks recently of unbroken sleep again but then it regressed. We think she's been having night terrors as when she wakes its pretty early into the evening and she is so upset immediately after waking.
Last night, she woke, I went into her room and she was happy to lie in bed with my hand on her hand/leg/bum. After an hour and a half, she was back down, but then woke again 20 mins later!

I wish there was a way to fix this. At 21 months, I would have thought the constant broken sleeps would be gone.