Re: herbal tea for infants??
Yep, I never gave my daughter any herbal teas… not when she was an infant and not even now when she’s MashaAllah almost 5.
I usually don’t give medicines also unless absolutely needed (if she’s in pain or something like that). I also started juices very very late, like around 8 months of age… and used to give just once a week or once in 2 weeks… she still loves plain water over juices, mashaAllah 
I only gave her cereal and baby food for semi-solids when she was a baby, for liquids it was always either my milk or plain water.
But then my daughter was not colicky, so its your personal choice… I’ve forgotten when I started mashed banana, that does help with constipation too.