It's funny how life's little opportunities present themselves, my best sexual opportunity of my life came out of the blue one night with an eleven o'clock telephone call from my son who was working away from home in France for a month. Tim's mother and I split up when Tim was quite young and divorced several years ago, the last three years have been very dry for me sexually, you get very few opportunities once you're past fifty to get new experiences. My son was married to Sian, a petite little auburn haired woman of twenty five, when I first met Sian, Tim was 27, he had picked Sian up from school, she was under five foot tall, totally flat-chested and looked around thirteen or even younger, I couldn't believe it when Tim told me that she was actually seventeen. They married two years later and they had their first baby exactly nine months after their wedding, little Isabella, a little sweetie, her birth caused a massive change in Sian, she went from a thirty-two – a cup to a thirty-four – D in just nine months, Laura came along two years to the day after Isabella followed by William two years and three weeks after Laura, so they had a perfect little family although when William was fifteen months old Tim told me they were trying for another son, "Just to balance the family up!" While Tim was working away he got into the habit of phoning Sian and the kids every night when he got in from work, it was eight o'clock in France so Seven o'clock in the UK, he got to say a few words to the girls before they went to bed and then a very short chat to Sian, well that was until the night in question! Tim phoned me at eleven o'clock at night, he had phoned Sian as usual but she had told him that the girls were already in bed sleeping, Tim caught a hint of excitement in Sian's voice which worried him slightly, well worried him enough to make him break his usual habit and phone back an hour later, he got no reply, so he phoned again an hour later and then again after another hour. Eventually he phoned me because he was a little worried, he told me where he kept a spare key and asked me to make the thirty-mile journey to his house to check if everything was OK. I arrived just before midnight, Sian's car was parked too close to the end of the drive, if I had pulled in behind her my estate car would have blocked half of the pavement, not that too many people would be walking past after midnight but I decided to play it safe and put my car in the side street a few yards away. I knocked the door and rang the bell, there was a light on in the hallway which lit up the front door, there was no response. I made my way to the back of the house, knocked at the back door, again no response; I found the hidden key and let myself in through the back door. I checked the children's bedrooms, all the bed's were empty, I went to Sian and Tim's bedroom, again no one there, the light from the hall showed that the dressing table was covered in make-up, there were skimpy dresses hanging up on the back of the wardrobe door as if Sian was deciding what to wear, I made my way to the living room, I was about to ring Tim and tell him the house was empty when a set of car headlights lit up the dark room. I watched Sian stagger from the passenger side of the car, she was obviously drunk, staggering in five inch heals, I caught my breath, she wore a stunning little black cocktail dress, very low, square-cut front and about seven inches above her knee, with the bright red lipstick and blue eye shadow, I could see the tops of the hold-up stockings showing below the hem of her dress even when she was standing up straight. I was about to go and meet her at the front door until I saw the man step out of the drivers side of the car, he was over six foot tall, African or Afro-caribbean, he met her at the front door just as she dropped her keys, they kissed passionately before Sian stooped down to pick up her keys, I took the opportunity to change tack. I moved quickly and quietly into the bedroom that Sian and Tim usually shared together, I closed the curtains and sat on the windowsill, I just hoped that Sian didn't remember leaving her curtains open when she went out, then a thought struck me, what if they didn't come into the bedroom, she may not have wanted to defile her marital bed with the man who had to bend down to get through the low doorways in my son's cottage. I heard the argument. "I've changed the bed linen in here!" "No way, I don't want to do it in a single bed and all those stuffed toys will put me off!" "Well, how about the living room then?" "No way baby, you have a nice comfortable bed in there, come on!" They entered the bedroom. "Remember, you promised to use a condom, I'm just starting my dangerous period so I can't do it without!" "Just use the morning after pill tomorrow, I have a box full in my car!" "I can't do that, my husband and I are trying for another baby at the moment, you have to use a condom!" "That dog won't hunt, I don't ruin my pleasure with an overcoat, my way or no way!" I opened the curtain a fraction, Sian was already naked, it wasn't as if she had a lot on to start with, just the dress, a black lacy thong, the hold-ups and shoes, she still had on the hold up-s and shoes but for the rest she was totally naked, the black guy was just pulling his trousers down, he didn't so much have a cock as a flagpole down the front of his pants. I waited for him to cover Sian's body with his own, he was aiming his cock at the promised land when I stepped out into the room. I was holding my mobile phone up to my eye and as soon as I stepped out into the room I pressed the camera button, the camera made a satisfying click-whir sound, the picture was perfect, petite alabaster coloured Sian covered by a coal black giant of a man. In the ensuing confusion I managed to evict the naked black man, throwing his trousers and shirt out after him. When I returned to Sian's bedroom she had pulled on a dressing gown. "Oh no, it's too late for that, get that dressing gown off right now!" Sian looked confused, I turned the camera screen towards her. "What do you think Tim will say to this?" Sian looked very worried, even more worried when I started to flick through the contacts and Tim's number came up on the screen. "You wouldn't, it'd destroy your son's family if he saw that!" "Your family too, your cushy life here, it's up to you, all I want is what you were about to give to that nigger for free, and it won't matter if I get you pregnant, it will all be in the family as it were!" I waited with my finger resting on the dial button. "Well, what's the answer?" Sian slipped the dressing gown off of her shoulders and was once again naked. I pressed the call button on my phone. "Nothing to worry about Tim, just the phone pulled out of the wall socket, I'm going to get my head down on your sofa and go home in the morning!" I turned the phone off and stripped naked; I made Sian suck my cock until I filled her mouth with cum, not that I particularly liked getting a blow job but it proved that Sian would do whatever it took to keep me happy. It also took the edge off of my appetite; it would mean that I would hold off my climax longer and have more fun inside of my daughter-in-law. As soon as I started to fuck Sian her breasts started to leak milk, Sian was still breastfeeding William even though he was fifteen months old, it turned out that she had been breast feeding constantly for five years, breaking one child of the breast only when the next was ready to go on it, her nipples were like leather but were also incredibly sensitive, when I started to suckle against her, drinking her milk, she went wild and began climaxing wildly almost tipping me over into my own climax before I was quite ready. I needn't have worried too much though, after I finally climaxed, filling her pussy to the limit with my sperm she started sucking me again to get me back to full hardness ready for another go round. We fucked five times before I had to go back to my home town to work. *** Over the next few weeks I fucked Sian about a hundred times, by the time Tim finished his French contract Sian was pregnant, she didn't tell Tim right away, she needed to fuck him a few times first, she left it a month before she told him, during that month. Every time my son Tim spent a night away from home I popped in to keep Sian from straying outside the family, Isabella, Laura and William also love having me around too, I even moved just around the corner from them all so I could be right there on the doorstep. Sian told Tim that Victor was a month premature but Tim didn't believe her, he told me that he suspected something and I persuaded him to send of DNA samples of Victor and him, the results were as I expected, my DNA and Tim's was too close to show Tim that he wasn't the father. We're all living relatively happily now, Sian had a fifth baby, mine again, even though I'm almost thirty years older than Tim Sian much prefers to have sex with me than Tim and she is wearing me out, I'm sure that she will fuck me to death but what a way to go!