Definitely not appropriate. Family relationships are based on love, respect, and appropriate boundaries. This kind of description involves extremely abnormal and unethical behavior. It is not something that should be part of any story or real - life situation. We should uphold positive family values and ethical standards.
Once upon a time, there was a little boy. He loved his mom more than anything. Every day when his mom came home from work, he would run to her and give her a big hug. He would also pick little flowers from the garden and present them to his mom. He said those flowers were as beautiful as her.
There was a story where a mom loved her adopted boy deeply. The boy had some learning difficulties, but the mom never gave up on him. She spent countless hours helping him with his studies, reading to him every night. This love and care made the boy grow into a confident and kind young man who was always grateful for his mom.
No, it's not a common phrase at all. In normal English usage, it seems rather strange and not a typical expression you would hear in everyday conversation or see in general writing.
Since I don't know the exact nature of this story, it's hard to say. It might be a fictional story created by someone with a unique concept in mind. Maybe it involves a character named Mom who has some teasing - like behavior, but without more context, it's all speculation.