It's a fig! Exact leaf shape and texture don't conform to any standard and are quite variable, especially with seedlings. I've seen that much variation on a single plant. The side views clinched it for me, since the stem, the petioles, and the new bud all have the fig gestalt. The major difference between fig and mulberry is size: fig has bigger, thicker growth all around. New mulberry leaves have two upward pointing bracts where the petiole connects to the stem.

Depends what sort of a Zone 8, esh_ga. In my zone 8/9 they are extremely common and easy to grow. PNW has zone 8 areas, I believe, and I am pretty sure lilac grows there too. We don't know where the OP is situated or even if the pic was taken where they live.

http://thewildpapaya.com/?product=euphorbia-leucocephala-little-white-christmas-shrubpascuita-tree

Opuntias are unlike other cactus in that they like a nice root run. They get as large as the pot will allow. In the ground plants get much larger quicker that potted plants.