Agggh, I decided to duo ranked with my brother, since we usually do quite well. We didn't do too terribly. We lost the first match, but the second and third we won.
The fourth started off incredibly rocky, me as Warwick, my brother as Sona. After a bit of farming and us veto-ing the surrender votes, I managed to turn the game around, scoring 4 aces 1v3 against their fed Riven, Vayne, and Mundo. We needed one more good fight to seal the win after I managed to push into their base after my last ace. My brother saw that I had pushed the opposing top inner turret and left it low due to being chased away, and made a comment that he wanted to take it out. I told him not to, since the game was won and we needed to stay together. He agreed after a bit of persuading and we caught the enemies at our blue. We engaged and took out one, but we started to fall behind a bit. I fell back to recover some health and find a target to pick off with my ult while the rest of my team stalled. While I recovered nearby, I noticed that there hadn't been a Sona ult or any heals being sent out. I check the scoreboard; no death timer on Sona. I check the mini-map. A full HP Sona is gliding her way to the enemy top inner tower on the opposite side of the map. She abandoned us, mid fight. This resulted in us dying 4v5. The enemies took the opportunity to destroy our nexus after killing Sona, who had just recalled. But hey, on the upside, he got that tower!...
The entire enemy team was even shocked at the fact that we lost after I had turned the game around and gained a huge lead on them. I am officially never playing ranked with my brother.