You wonder why every play date ends with one of the children crying and screaming for a toy that the other is just not willing to share. Your baby is also the same. She is still not willing to share her toys with other children and no amount of reasoning will make her part from the toy for even a second. She is possessive about her things and is still not confident to share it with anyone else.
What you need to know
Do not expect your child to understand the concept of sharing yet. Right now your toddler is focusing on her physical development, mastering control over body parts, handling helself and also learning to talk. Empathy and social skills will come later.