What are the benefits of caring parents? The Dhamma says that not helping parents is evil and preaches to take care of the elderly parents. What can be some positive outcomes the children will get by helping the parents?
The Buddha says that there are two people that you can never repay, no matter what you do. They are your mother and your father. Again the Buddha said that there is one way that you can repay for all what they have done.  That is to establish them in this Dhamma Path. It is not an easy task, as we are all full of defilements that muddy the waters and prevent us from seeing this path. So if they’re stingy for example, then you can try to find some way to influence them to be more generous.  If they are not the type to observe the five precepts, then you could try to get them to be more virtuous, to have more principles in their lives. You can gain merits that will help pave the way to your own Dhamma path, if you could help introduce your parents to the practice of Dhamma. Try to do it in as diplomatic a way as possible. Most parents resent their children who try to tell them what is right or wrong.  That is why you will have to find some means of doing this in an indirect way. If they are not into Dhamma, try not to say that this is a Buddhist thing. That is how SN Goenka thought Vipassana Meditation to the Westerners. Only later that they get to know that this is the Noble Eightfold Path that their Master is leading them to.