I'm finding it hard now too! She's so active and just on the go all the time. She's so busy I think sometimes she doesn't even know she's tired.
Sometimes she will start to whinge, rub her eyes, and ask for a feed when she's tired.
Other times there will be no signs, she will be playing happily and I will think 'she's been up for ages, it's time for a sleep'. So I pick her up for a bit to quiet her down and then she goes to sleep really easily so she must have been tired but just not showing it.
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