I agree that she has to over work to satisfy and provide to them their requirements but she also has to bear in mind that her son needs attention and motherly affection which is the most important for a child.
They can spend their time together on weekends, this is not a great deal...

I am a working mom too but i never come home late, i am more worried about their upbringing than satisfying their needs. They need more my time and want me to listen to them every single time they need me and i think listening and helping them to get an answer to their questions is more important.

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"Watching your daughter being collected by her date feels like handing over a million dollar Stradivarius to a gorilla."
Jim Bishop

She does not only have to say that she cares but she has to show it to him too, your friend should realize that her son does not has his father's affection anymore and she will have to give it to him. Love and affection is very important for a child.

See, the son is at a lost. He cant understand why his parents gor divorced, why his father does not live in the same house as them. He is also wondering why is his mother spending so much time at work. SO many questions in his little mind and no questions. The son needs love, he needs to know that his mother is there for him. I believe that one way of solving this problem would be that the mother talks to his son. Tell him about this new situation, why is working so late at night. Communication would solve that problem.

Hope is right, normally children who are living with divorced parents have the tendency to feel dejected, they would want and look for more attention and love.
If you would not give him more time, he would surely go astray!
So, plan your time and your child needs you, don't forget about this.

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"When I was born I was so surprised I couldn't talk for a year and a half." - Gracie Allen

she must talk to him and explain to him that since his dad is not with them she has o work more and more to provide for his needs and thus she cant be there always for him. i am sure he will understand and make a beter effort.

I think that she must put in some more effort so as to give the son more attention.It is true that money is important but the son also need some love and comfort.That is what he is trying to say through these bad results.
She must find time for her son.

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