You've long suspected that your stepmom only married your father for his money, and you're not surprised when she openly admits it to you. The problem is that he only married her because he wants to have another baby, and so far their attempts have failed. Your stepmom is quite sure the problem is with his sperm, but he would never admit it. Your stepmom knows that her curvy, fit body makes you horny, and that you like having her around. You don't want your dad to divorce her, so you'd better help her get pregnant! He'll never know the baby isn't his! Lay back and let your stepmom stroke and suck your cock, then ride you until you nut inside her. You're going to have to do this as many times as it takes to get her pregnant - and then keep doing it afterward to satisfy your horny stepmom, since your dad clearly can't!