Doors locked when battery died

[lynhnn]

So my car was left in the cold for few days and the battery is dead. The charger was stuck in the leg room of the rear because the rear seats were folded down to carry some furniture. The back door is locked so I couldn't unload the furniture out to pull up the rear seats. The rear doors are also locked and not open-able due to the battery ran out.

I wish I can open the rear door regardless of having the battery there or not. Parents with kids would be extremely disbelieve if they know this.