It sounds like frustration. He is 14 and wants to be around his friends.
A bunch of little kids are driving him crazy, he probably does get tired of them.
He is not their parent. He is a big brother who has not been trained on how to be a parent or a caregiver. Unless you are very straight forward with "Men".. they do not understand by just observing and learning the fine art of parenting, and care giving, especially at 14 yrs old. He needs to know options for his frustrations, he Needs to know techniques on how to handle young children.. Some people attend college to learn this.. Others as parents learn as they go along.. But he is not their parents.
He will be a freshman or sophomore in High School? That is a big difference from kids in elementary school.
She needs to realize he is a young man now, and he needs to be treated that way, BUT he also needs to know that if he wants to be treated as a young man, he needs to behave as one. That means since he is not using FB correctly, he is not allowed on there until he can prove he can handle himself properly at home and on line.
His father needs to speak strongly to him about Pornography. He needs to realize this young man needs some facts about his body and about sex especially on line in case he were to get in trouble.. and about what this young man is experiencing. . Yes, this is the time, to open up this dialogue and not make it tabu when with his parents having mature conversations. This boy is reaching out for information, because he is not getting it at home. He is experiencing changes and needs in his body.
She needs to take time alone with him. She needs to accept he is a young man with needs. And she needs to figure out to reach out to him so that he can talk openly with her. Yes, we have tons of friends and relatives with sons that are now in their early 20's.. The conversations started off very basic about sexuality especially once they were finished with the 8th grade. These conversations have grown from there, so that the parents are pretty blunt about expectations.. No hemming and hawing about it.
In 4 years he may be gone to college. These are her last few years with him as a "child" in her home. AND make sure the father has a strong influence on him.. This young man needs to know his dad has his back, because his dad is all up in his business, keeping up with him.
Parenting is not for the faint of heart. We set the ground work on everything..