Paraguayan here. Nice to see a good article talking about Yerba Mate. A nitpick on Tereré. Tereré is usually the ice-cold version of mate. You drink mate with hot water, tereré with ice-cold water as a refreshment. The practice of drinking it with fruit juice or some sweet beverage is mostly prevalent on northern Argentina. Here it is mostly viewed as a sacrilege. You drink your yerba mate, whether hot or cold, unswe…
Parts of southern and central-western Brazil also drink Tereré ("Tererê") with fruit juice, most tipically lemonade, so I'd guess there may be some other places here and there in South America where that's also regionally true In those same regions a sort of sweetened hot mate drink is typically made for children. Do you have that in Paraguay? It's called "Mate-doce", and I'm pretty sure it's not related to what you…
We also have "mate dulce" but it's mate usually only in name. It's made with coconut and other stuff, but drank in a mate gourd. As far as I can tell (I'm no expert, never made or drank the stuff) it does not carry yerba mate at all.