We probably will never know about the mother and child, but I am sure that Disney did everything possible to assure their safety.
Disney was the first cruise I took 19 years ago on the Magic when my son was 12, he is now 31. This will be our 3rd Disney cruise and we have been on RCL and Princess several times. Those cruises were fun, but no one has matched up to Disney. It is definitely worth the extra expense. They treat the children like royalty and everyone is special to them. I have never had any issues on any cruise line, but Disney I always felt special. The atmosphere is different and only Disney can create that atmosphere.
RCL is my next favorite, they were lots of fun and I believe the crew went above several times. Princess is okay, they did their jobs, but didn't feel welcomed. I probably wouldn't do Princess again.
Try Disney. Thanks