Please identify this weed

Question

The stems are red, leaves oval and opposite with light veining. The sap is milky.

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Answer 1

Milkweed.
It is being welcomed more and more to garden landscapes and flower gardens as a source of food for Monarchs.

Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/flowers/milkweed/growing-milkweed.htm