Nest Mate Black Chinned Brothers?

These little guys only 1/2 heartedly spar with each other, and perch unusually close to each other just outside my window.

They appear to be black chinned adolescent hummingbird males.  They have very small "goatees" of bright feathers under their chins, unlike the full grown adults who look like they spilled a quart of cranberry juice down their china and throats.  They do the little "are you threatening me?!?" head bobs...  but they'll sit on adjacent branches, and easily within stroking distance, but they only 1/2 heartedly 'fight'.  Then a Rufous or Anna's hummingbird comes by, and it's a melee, with "Battle of Britain, 1939 Spitfire vs Messerschmidt - esque" dogfights chirping and speeding and whizzing about the back and side yards.  Once the "interloper" is driven off, one or both of the young males comes back, to roost above the feeders.   They are not really a "team" but they are not really "rivals" either... they are pretty much just peaceably co-existing - better than my brothers and I ever did!  If a female black chinned hummingbird shows up, they'll Swoop Down, and chirp "hey baby...  how you like my feeder? you in estrus yet, hmm baby?"

I'm going through about 1/2 a gallon of nectar a week now, out of the 6 feeders in my back & side yards.  That's a pittance compared to some bird fanatics who go through 2 gallons Each Day (as Birds and Blooms has told me).