Most herbal teas are safe for children. I would steer clear of single herb teas marketed for medicinal use unless you know the herb, although they will usually be labeled.
I give my daughter catmint, oatstraw, lemon balm, echinacea, chamomile etc. It is part of her bedtime routine to drink warm, sleepy tea...although it doesn't seem to make her sleepy.
Green tea, white tea, black tea, and twig tea have caffeine in them, just for your information.
Temperature: The first time I make a batch of tea, I put some hot tea in her Klean Kanteen and add cold water until it feels warm, but not hot through the metal -- if I can't hold it comfortably, I think it is too hot. Then I put the rest of the tea in a jar in the refrigerator and on subsequent days I put some cold tea in her Klean Kanteen and add boiling water until it is the right temperature.
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