"baby" b not so much of a baby anymore

All of my b's are growing up way too fast. Queen b is now a kindergartner, busy b has started preschool, and my baby b is no longer a baby!!! He will be starting Mother's Day Out again next week and will be in the 2 year old class since he will be turning 2 next month. In the 2 year old class the kids begin taking a nap on their nap mats!!! (No more baby beds at school.) For Berkley and Beckham this was not a big adjustment, because at age 2 they were both already sleeping in "big" beds. (Simply because they had a sibling on the way and we needed their baby bed!!!) Brenner, on the other hand, is our "baby!" He definitely fills the role of the baby of our family too. Since he will be expected to "grow up" somewhat when he starts his new class next week, I decided we might need to practice. So...we got his new nap mat out yesterday and tested it out at nap time. Absolutely no problems!!! He went right to sleep. I only went in his room once to help him get back on top of his mat. Could it be?!? Is my baby b really no longer a baby? Is he indeed ready for a "big boy" bed? I don't think I can take any more major milestones this week!!!