There are several chili trees growing wild in some nearby bushland.

One appears to be Siling Labuyo



another looks like it is Chiltepin Chili



and there is this third plant which always grows in the same spot as the chili trees, and looks almost identical to them except it has a black berry (when ripe) that grows in a cluster of 4. It has virtually identical flowers, leaves and woody stems. If you saw the three trees with no fruit on them in good condition, you couldn't tell them apart.

I couldn't find a good example to photograph as bugs have eaten most of their leaves, but the unknown plant is on the right and Chiltepin chili on the left - Any idea what it is? Just a type of weed?