First, I want to let you know that the average age that boys day train is 38 months. Average night training age is over 4, closer to 5. Having that in mind, I tried training with my son when he was about 2 months shy of 3, but it was quickly apparent to me that not only was he not ready, but I was 7 months pregnant and didn't want to force potty training when so many changes were coming. I also didn't want to take the chance that he would regress once his sister was born.
He knew how to use the potty; would even occasionally tell me he had to go, but it was usually me or his dad who initiated. He absolutely REFUSED to poop on the potty, and it frustrated me to no end! He would go behind his train table, squat down, and poop in his diaper. He would then tell me in perfectly understandable English, "Mommy, I pooped. I need a new butt." I was just done!
So, at Christmas (his sister was 6wks old), I told him that when this box of diapers ran out, I wasn't buying any more. Every day, I prepared him by telling him he only had xx amount of diapers left.
The day of truth came on President's Day (5.5 wks after I first told him; yes, I know I had WAY too many diapers, but buying in bulk was best for our pocketbook!!). He woke up that morning, and I pulled out the last diaper. I told him: "Look! Last diaper!" He acknowledged by telling me that he had to use the potty now.
Later that morning, he started to go behind his train table to poop (even though he had already peed on the potty twice), and we caught him. Immediately, we picked him up and put him on the potty. He refused, crying and carrying on, and I felt like such a bad mom. But I knew that I had to stick to my decision, and we made him sit on the potty until he couldn't hold it any longer (about 30 minutes). He pooped, it splashed him on his butt, and he thought it was HILARIOUS! "Mommy, it splashed me!!!" And that was the end of it.
We've had a couple accidents in the last 14 months, but accidents is exactly what they've been. Part of me wishes I would've run out of diapers a couple months earlier or maybe even before his sister was born, but I accepted that he probably wasn't ready before then. I'm glad I went the route I did, though, and I honestly don't know what I would've done had it not worked!