If God Created Everything, Doesn’t That Mean He Created Evil?

Questions about whether God creating everything means he created evil too, and how a grief counselor can answer a question about whether God causes or allows death and sickness. How should my daughter answer a friend at school who said, “If God created everything, he must have created evil too, like cancer, right?” As a grief counselor, how should I answer this question I’m often faced with: Does God cause or allow death and sickness?