"My boy"

Today my dd4 found the box of Maisy valentines and pulled out six of them. She indicated that four of them were for the four members of our family and then said that another valentine was for Robert. When I asked who Robert was, she responded that Robert was "her boy". Further questioning revealed that Robert was a little boy in her Sunday School class. I didn't expect to have my four-year-old wanting to give valentines to any specific little boys quite this early!