A major life change or a setback can be a reason. For example, losing a job or going through a divorce. In such tough situations, people might turn to their moms for comfort and support, just like a little girl would. They feel safe and protected in their mother's presence. This can lead to that state of being mommy's little girl again. And it's a natural reaction as the mother - child bond is one of the strongest and most nurturing relationships.
It could also be due to a psychological state. Sometimes, when we are feeling extremely stressed or overworked, our minds might subconsciously seek the comfort of our childhood, and our moms are a big part of that. So, we might end up acting like mommy's little girl, relying on her for the warmth and security that she used to provide when we were actually little girls.
One possible reason could be illness. When a person is ill, they often become more dependent, like a little child, on their mother for care.
Magic is a common reason. Maybe a mischievous fairy or a clumsy wizard cast a spell wrongly. Another reason could be a strange scientific experiment gone wrong, like some sort of radiation or chemical reaction that alters the body's form. Or it could be a curse from an ancient artifact. If someone disturbs an old tomb and takes an enchanted item, it might put a curse on them and turn them into a little girl.
The theme of family relationships is likely to be prominent. It could explore the power dynamics within the mother - child relationship, how this transformation affects other family members, and how the family as a whole adapts to this new situation where one member has become mommy's little girl.
I'm not sure specifically which 'I was turned into mommy's little girl' story you mean. It could be a fictional story about a transformation, perhaps magical or psychological, where the protagonist starts to feel or be treated like a little girl by their mother. Maybe it involves a regression to a more innocent and child - like state, but without more context it's hard to say more.
In some turned into a girl stories, it could be due to a curse. For example, if someone offended an old witch or a powerful spirit, they might be cursed to change into a girl. Also, there could be a strange natural phenomenon. Like in a place full of strange energy, a person could be transformed into a girl just by being there for a while.
One possible reason could be a magical accident. Maybe mom was trying to do something else with a spell or charm and it backfired, turning the person into a girl.
A scientific experiment gone wrong. If he was in a science - fiction type of setting, perhaps some crazy scientist was testing a new device or formula that had unexpected side effects of gender transformation.
Another theme might be protection. The mommy protects her little girl from harm, whether it's physical danger or emotional distress. For example, she might shield her from mean kids at school or console her when she's feeling sad. This theme emphasizes the role of the mother as a protector in the little girl's life.
The themes could include adaptation. Since being turned into a little girl is a huge change, the character has to adapt to a new physical form, new social expectations, and new ways of thinking. Also, the theme of discovery could be present. Discovering the world anew as a little girl, things that were overlooked before might become important now. There could also be a theme of loss, losing the status and abilities that came with being an adult.
Family problems can also play a part. For example, if there's abuse or neglect at home, it can make her lose faith in goodness and turn bad. She may act out in rebellion as a way to cope with the pain.
It could also be due to past experiences with men that were not positive. If she had bad relationships or experiences with men that made her feel unfulfilled or unhappy, she might be more open to exploring relationships with women. Also, some psychological research suggests that there may be some inborn factors that could play a role, but it's still a complex area of study.