I was baptized at the ripe old age of 11. Several years after I was DFed, I met with two elders from my congregation when I was considering trying for reinstatement. I mentioned that I felt it wrong that I was held responsible for a decision made when I was 11. (I was baptized in 1975, before the baptismal wording was changed to make it a contract with an organizational club.)
The elders explained that there was no way they could negate the baptism. However, if I felt I hadn't made a mature decision, I could get re-baptized. I decided against double-dipping.
Ginny