The Buddha said that his disciples should repay their parents’ kindness. He said: “Even if you were to carry your mother on one shoulder and your father on the other shoulder for 100 years, and were to look after them by anointing, massaging, bathing, and rubbing their limbs, and they were to defecate and urinate right there [on your shoulders], you would not in that way pay or repay your parents.”
Those who fail to take care of their parents would have failed their fundamental duties as human beings. One such way to pay them back is: “Anyone who rouses his unbelieving mother and father, settles and establishes them in conviction; rouses his unvirtuous mother and father, settles and establishes them in virtue; rouses his stingy mother and father, settles and establishes them in practicing giving; rouses his foolish mother and father, settles and establishes them in wisdom: To this extent one pays and repays one’s mother and father.”
As you can see, it is not easy to repay our parents’ kindness. That is why Shakyamuni Buddha left two great Dharmas: 1. Medicine Master Buddha Dharma to help take care of their current needs and 2. Pure Land Dharma to help send them to the Pure Land where they will be with Amitabha Buddha until they become a Buddha themselves.