Playing with my sister

I'm Robert now 28 and I live with my twin sister Carmen, since the age of 15 Carmen and me would play together. We are average looking and weight and started exploring each others bodies. Not fucking, but everything else we could thinks of at the time. Our parents were in their late thirties when we were born and we're their only children. They had their own business that took up most of their time and we were left to our own devices as they say. Both Carmen and me were the quiet type and didn't mix much with others of our age. I was and still am in to model building and one day while painting a model ship I spill paint thinners on my clothes and it started to burn my skin. I rushed to the bathroom and starting showering in my clothes. Carmen had been watching TV and had heard me yell and seen me running, came to see what was wrong. On entering the bathroom, seeing me showering fully clothed, it was her who said I should remove my clothes and she took them away to run thru the washing machine. She returned short time later and she checked over my body for problems. She started to examine my cock and while she was checking it, it went hard and she was amused by it. She then undressed and joined me in shower and started to play with my hard cock. I started to feel her up and after she had got me to blow my load, we left dried ourselves and dressed. Nothing else, then a few days later we were home alone and I decided to shower after I had been tiding the garage for my father. Carmen asked could she join me in the shower and I agreed, again I got an hard-on and she got me to cum. After the shower we laid on her bed feeling each other up. Over the next few weeks we progressed to her sucking my cock and me licking her pussy. It became a regular thing for us to play with each other and showering together. I started thinking of asking her to let me fuck, but didn't asked her incase she stopped our playing together. I send away for books on sexual acts and even some condoms, but sexual intercourse wasn't involved for several years. When we first fucked it was anal sex, Carmen had heard stories of condoms breaking and didn't want to risk it. As it happened the first time I fucked her ass, the condom did break. It was one the ones I had got before and on looking at the box was out of date. Carmen said I could fuck her ass without condoms and we continued for several years doing that and oral sex. Then our mother died suddenly and we began to stay together more. Then our father sold his business and we moved to another town. He became ill and also passed away. We were now alone together with both parents now deceased and only 20 years old, we worked at the same place and and lived together and slept in the same bed. Carmen worn mom's wedding ring and everyone thought we were married. On our 21st birthday I took Carmen virginity and with her now on the pill, sex became more regular. I got a job in the city and we both moved there. Carmen didn't have a job in the city and would stay at home and wait for me to get home. She saw other women with their children and decided she wanted to have a child. She asked what I thought about it and we done some checking and decided to risk it. With all the tests now available if anything was wrong it would be found quickly. She got pregnant within a couple of months and we had a baby girl and nothing was wrong with her. When our girl turned 1, we started trying for another and now Carmen is 5 months pregnant with twins and both are healthy.