Start on the left most (West) side of the cave. Grab some jugs and move up high and slightly right to a nice rounded like hold. From here work the face crimps and left hand under clings to the finish. Exit by traversing left to a gradual down climb to safety. Fun. It has the best landing of the lot!!
From the 1st parking lot follow the Sisters Trail for a few hundred yards or until you come to the Ponderosa Trail junction just below and to the EAST of the "Brothers Lookout" formation. Turn west (Left) onto the Ponderosa Trail for about 30-50 yards before you began to head NORTH (right) up the steeping slope. Try to stay as EAST as you can so you enter the 2nd Tier gully at a gradual pace. The "Brothers Under Belly Cave" is located up (West). It's an obvious mini cave on your right. Enjoy