Quiet Family Friend

All my life, I have known her (39); she was thought of as an aunt by my younger sister and me. She was always a quiet person, not shy only spoke when she had something to say. She is a year younger than my mother and had never married. Aunty, as I will call her, was always nervous when visiting the city and usually went with my mother. But I was 21 and going to the city to pick up stuff for the family business. Aunty also had to go; my mother was ill with the flu. So Aunty would go with me, no problem, but it meant us staying overnight, as Aunty had two appointments. One on the day we arrived and the other the following morning. So, we booked into a motel, one room, two beds. While she attended her first appointment, I picked up the stuff I had come to get and went back to get Aunty. She was still waiting for her turn and went just after my return. Afterwards, we went to the motel and settled in. I hadn't been told the reason for her appointments and didn't ask about them either. But Aunty wasn't the happy person she usually was after the first appointment. After having dinner at the local diner and getting back in our room. She told me she was trying for a child via IVF, but changes in the law in our state now prevented her from getting IVF as she was single. She then straight out asked me to get her pregnant; I was shocked. But after thinking it over decided to agree. I wasn't a virgin, but also wasn't a stud. Aunty was my third fuck, as well fourth and fifth fucks.
The fifth fuck was in the morning before we checked out and went to her dental appointment. Then we returned home; over the following weeks I visited Aunty several more times to fuck her. Only stopping when a test kit showed a positive result, Aunty is pregnant, and everyone is happy for her. Only Aunty and I know that I am the father of her child; everyone else thinks it was the IVF.