I am a single mom living with the father of our only child. He is the main earner in the family but I provide the childcare and work part-time. We have no plans to marry and may not be together much longer. He has expressed a strong desire to claim our son and says "we" will get more money back if he does. I feel I should claim our son as a financial safety net in case he leaves us. Who has the right to claim our son and is there any validity to the more earned more back theory?