Here in Germany, babies are given teas. When I first arrived in the 70s, no one would have even considered drinking tap water. Teas made with fruit, herbs, particularly fennel or chamomile (like Peter Rabbit!) were the norm. They are unsweetened and the water has been boiled.
In France, on the other hand, Evian water was what babies have always been given.
Nowadays, however, both fennel and chamomile tea have fallen into disrepute, despite generations having survived them, and even German mothers give their children water.
When would you start giving a child "normal" tea?