I personally have never heard of this so I looked it up and
Prevention
Breast milk jaundice cannot be prevented. When the condition occurs, it is very important to recognize the baby's yellow color as early as possible and have bilirubin levels checked right away to make sure that there are no other liver problems.
Breast feeding jaundice can be limited by making sure your baby is getting enough breast milk. Give your baby unlimited time at each breast, and feed approximately 10 to 12 times per day starting the first day of life. Get help from a lactation consultant or your doctor as soon as possible if you have any difficulty.
Now I have had 3 kids and breastfed all of them to 12 months and the only one that has jaundice was my middle child and all we had to do was keep him by the window so the sun is on him.
So My recommendation is feed the new baby every 2 hours as my doctor told me and the sites I found as well and when you put baby down in the bouncer wor swing or what ever keep some form of sunlight on at least 50% of the babies body.
Good Luck, My middle son had alot is "issues" that I was affraid of reliving too, and they have not, realx you have experience now that you did not so you will be able to catch it really early now and it should be easier. Deep Breaths and Congratulations please enjoy it and let the fear go. You do not want to miss out on the joy of what you have for the fear of what might be, I did and not one day goes by that I do not regret it.