When I was 12 the life I dreamt of changed on an almost weekly basis. Recurrent things I wanted to do included having babies, being a housewife, being a nun, travelling around the world, running my own company, being stranded on a desert island, and living in a eco-friendly treehouse without anyone else around (not necessarily all at once). It was the life I dreamt of, but that doesn't mean I should have gone ahead and done any of it at the age of 12 and it would have been appalling if the adults around me had let me, worse still if they had facilitated it. Being a child means not having the insight, knowledge, resources or life experience to know what is best for you, and your parents, teachers, doctors and other adults are therefore called upon to help make those decisions for you. As you get older you are gradually considered competent to take partial or total responsibility for more and more choices, from ear-piercing to surgery to voting to marriage. For sex, in this country, it's 16. Paedophilia cases can be and are pursued even if the age gap is quite small and the adult has written and video evidence and a sworn and signed statement from the child to prove that the child initiated contact, initiated the relationship, suggested having sex, bought the condoms, chose the position and gleefully jumped into bed with "yes please!" written across their torso... The reason for this is that adults - all adults - should know that a child does not have the capacity to make such grown-up and permanent decisions, and the adult therefore has responsibility to protect the child from the child's own recklessness. An adult should refuse to have sex with a child who is pushing his/herself at them in much the same way as you would refuse to have sex with an adult who was very drunk and emotional after a row with their partner. They are able to make many decisions for themselves, but they are not fully competent to take all the factors into account and make a rational, grownup decision about it. Even if the girl is not being abused in the sense of it being against her wishes, and currently feels quite happy with the situation, having babies in her early teens is against her best interests and she is not being adequately protected by the adults around her. That's what makes her a "poor girl". PS. I am not necessarily agreeing with the entirety of the standpoint I have just outlined, but it is the standpoint that the law takes.