Chemo and cancer treatments ruin fertility ???


I know this is a weird question.

My 26 year old sister in law was diagnosed with stage 4 bowel and liver cancer in June. She has come so far. The cancer is dying.

She always wanted another baby.

But would the treatment have ruined her chances of this happening???

I said something today- thank god not to her but I thought she would be fine. Silly me. Ive dealt with cancer for the last 4 years I should I know the answers but I guess fertility has never been brought up.

I am pregnant and I am hoping she isn’t crushed. She is a great mum and she wanted another baby years ago but held off. Is it too late ??