How do we, as readers, generally feel about predicting pregnancies?

I did a reading for my mum last year about her family. She wanted to know what was in store in her family life. I told her it looked good.
She asked me directly if I thought that meant my sister would have a baby.
I told her that pregnancies were like death-not something we "do" as tarot readers.

Secretly, I felt confident that it would happen. I knew I would have to wait and see what the future had in store.

I didn't have to wait long.

My sister found out she was pregnant a few weeks later. She had not been trying, but was happy for it anyway.

Has anyone here predicted or seen a pregnancy? Is that one of the rules of tarot?

Two things:
One I'm still very much learning, and two, I don't remember the exact cards (I did a three card spread).