It had started several nights before the school year had started, my mom and I had been by ourselves in a motel room, I had started getting ready for bed when my mom had asked me to sleep with her, I still had on my short shorts when she still had on her short shorts and bikini bra. Then we had both taken off our short shorts, I was in my striped speedo, my mom was in her bikini. When we'd both gotten in bed that night, we'd caressed each other, her tits were sexy hard in her bikini bra, my dick was huge and hard in my speedo. We stayed at it till we were both asleep. This had all happened when my mom was in her mid 30s, when I was in 7th grade at age 12 and 13, way back in the early 70s.

Around 1 month after school had started, my mom had gone around the house in her bikini, at that time, I'd had no way to tell she was pregnant.

Almost 2 months after school had started, my mom sat me down one day and let me know she was going to have a baby and that she would have the baby in the very next June when the school year had ended. When she'd told me this, she'd already pulled off her blouse and skirt. I'd gotten all hard in my short shorts and had stripped to my briefs when I'd seen my mom's stomach all squishy between her panties and bra.

After she let me feel her baby, I went to my room and had enjoyed rubbing myself in my briefs, I couldn't help myself. I remembered around those several nights in that motel room before I'd entered 7th grade, my mom was had shown off her sexy flat stomach in her bikini, it made me get all big and hard in my striped speedo.

At age 11, I'd started cumming, sometimes in speedos, sometimes in my briefs, I had always some how cleaned it up so my mom wouldn't know.

There had been a few times when my mom had gone around the house in her panties and bras and still showed off her still flat stomach after she'd told me about her pregnancy, I had gotten hard in my short shorts just from watching her feel her baby.

The day I turned 13, my mom let me look at her stomach as her pregnancy had just began showing, she'd had on pregnancy panties and bra when I had on briefs, was I all nice and hard in my briefs from feeling her baby as my mom's belly had already started blossoming.

When her pregnancy had started showing and she'd started getting a belly, she'd started wearing seethrough nightgowns, so I still saw what was underneath. When she'd said goodnight to me, I would take a glance at her seethrough nightgown, I had seen what her belly had looked like in her pregnancy panties and bras. I'd started rubbing myself every night till I had fallen to sleep.

Then around Easter vacation when my mom was 6 to 7 months pregnant, I was in my speedo and was ready to put on my basketball jersey when my mom had asked me to her room. There she was in her dress and had asked me if I wanted to look at her belly. I told her I wasn't up to it when she said it was ok. Then as she pulled off her dress, out came her nice slim legs, big pregnancy panties stretched around her belly, a three inch swath of bare belly and bra, was my dick hard in my speedo.

Then she'd had something else to tell me, she'd asked me if I had remembered our night in our motel room those several nights before I'd gone back to school, I told her yes. Then she had told me I was the father of our baby, that the baby had happened in her stomach on that night when we'd both been in that motel room.

My mom had smiled when she told me that and that she'd wanted to be pregnant. We both kept this from my dad who never knew I was the father of what he'd thought was his baby.

After hearing the news, I'd stared at her 3 inch swath of bare belly knowing that went from a flat stomach to a round belly when I was hard in my striped speedo.