A.,
It's so tough as a parent to know exactly what to do when we're confronted with challenges that are perplexing, and have possible longer term consequences for our children. I myself have some of those I'm working on with my own, just about, two-year old. As I've considered how to proceed on each issue, I've decided that I will always follow one particular rule or value as my measuring stick in determining the right (we always hope) course of action. My ultimate value is this: Whatever course of action I choose to pursue, the ultimate outcome I want is to maintain for my child a feeling of safety, wholeness, value, and trust that they can and will make important growth steps when they are ready. What I am not saying is that to obtain this outcome it means we have to sacrifice discipline, rules, boundaries, or appropriate behavior. On the contrary, maintaining this value as I discipline, set and maintain rules and boundaries, and help shepherd my children's appropriate behavior, I have found that we are both freed from a significant amount of stress, anxiety, and contention. In other words, as you make your decision about what to do, be really clear about what your ultimate objectives are with your child--let these ultimate objectives be your guide. They are far more important than issues of sippy cups, finger sucking, and temper tantrums.
Blessings to your efforts.