When you make a big deal out of your toddler’s favoritism by reacting with intense emotions, you may make it worse. Since toddlers' language skills are still developing, they're extremely attuned to your facial expressions, tone of voice, and body language. This means toddlers may pick up on your discomfort with their favoritism.
At the same time, it’s important for you not to collude with your toddler’s favoritism. For example, you shouldn’t go out of your way to give in to your toddler’s demands for the preferred caregiver when the non-preferred caregiver is available and equally capable of meeting the toddler’s needs. In fact, when the non-preferred caregiver is avoided simply because the toddler prefers the other caregiver, it may inadvertently reinforce the toddler’s belief that the non-preferred caregiver is not to be trusted.