Does "on ley line" work for you?!

I have that lot trait, and my Sim has had 3 children in the house, one with just the lot trait (single child), one with the addition of the fertile reward trait (again, single child), and the third with the addition of my sim and her husband having the fertile reward trait (another single child).

This is really frustrating because I wanted to have twins or triplets but the lot trait seems to be jinxing me!