If you want kids then have kids. Are children with one IBD parent more likely to have IBD? Yes. Is it guaranteed they'll get IBD? No. In scientific studies the odds of passing on IBD to your children is between 5 and 22 percent (varies).
Here's a good read on IBD and families:
www.crohnscolitisfoundation.org/assets/pdfs/WomenandibdFamily-IBD-Link.pdf