When we ask "How are you doing?" it's often meant as a greeting rather than a question. But when asked sincerely, it's an opportunity to find out if someone needs help. By checking up with people, particularly family members, consistently showing that you care about their welfare, eventually your radar will improve and you'll know what to do to help.
Everyone has some challenge, and focusing a little of your time on someone else's challenges, helps keep yours at bay.
So, how are you doing?