How old was Patricia when she became pregnant with her third child in Born a Crime?

Trevor's mother Patricia was 44 years old when she became pregnant with her third son, Isaac. This came as something of a surprise to her as she'd had her tubes tied and so didn't believe that she'd ever get pregnant again. Isaac was Patricia's second son with her second husband, Abel Ngisaveni, a mechanic at Mighty Mechanics, a garage just round the corner from where Patricia's first husband—Trevor's father Robert—lived.
When Trevor was nine years old, Patricia gave birth to her first son with Abel, Andrew. At that time, all seemed well in their marriage. But as time went on, strains began to emerge. Abel had a much more traditional attitude towards gender relations that Patricia, who was always very much a free spirit. This probably helps to explain why Patricia agreed to undergo such a drastic contraceptive procedure; she knew that having more children with Abel would almost certainly increase his control over her.