Growing up, I remember carpooling to parties with other neighborhood friends. One parent would drive us there and drop us off, and another would pick us up. My parents loved it. It gave them some free time to do what they wanted while I was off having a good time. Today, parents not only seem to expect to accompany their tykes to a soiree, but to be well fed there too. Living in a large city with serious space constraints, party rooms frequently come with guest limits, leaving many of us wondering about the perfect age for holding a drop-off birthday party?