We will be in this exact situation,'although my daughter is 14 months. She is with my mom exclusively during the day, with storytimes, play dates, and loves music! #2 is not going to daycare, so the sibling spit isn't a concern. We are looking at a toddler class at primrose, and transition to preschool at 3, or wait and go straight to preschool. We talked to our ped, and she said she is getting the social interaction, so don't feel pressured to put her in a toddler room.