• The biggest roadblock in my house is resistance. Several times over the last year of potty training, when one of my sons started to progress, the other would regress. And although I didn't push either son and gently encouraged the one who was using the potty, after about a week, they would both refuse to have anything to do with it. My theory is that in addition to separating from me and becoming "big boys," twins are anxious about separating from each other. The one who is stepping out of diapers is also stepping away from his brother. So until one or both is ready to take the plunge, each attempt to train gets thwarted by the other's ambivalence.
• As soon as you can, establish a potty time (first thing in the morning). Since it takes longer for twins to get through all the potential roadblocks, they might need more structure. Get them used to it; make potty time a daily ritual that is fun.
• Separate them as much as possible during this time. Lessen the intensity between the two and give them more of the one-on-one they need to focus on their body. Twins tend to listen and focus better when they are apart.
• Get someone else to help. Because of all the work involved, parents of twins can get too involved in the process. As I found out, this is one of the reasons that kids can resist training.
• Although it is hard not to be frustrated and angry if one or both kids are resisting (and I have had my moments after changing two three and a half year olds' dirty diapers), the only thing to do is back off. I have learned that the more I want them to use the potty, the less they want to do it. Reassure both of them that they will "get it" when they are ready and that there is no pressure before then.