If you forgot flowers on your Mom's birthday, you can still propitiate her by sending a bouquet the next day. Propitiate means to appease someone or make them happy by doing a particular thing. Handy strategy for lovers, too.
One of the most common uses of propitiate historically was in the sense of appeasing the Gods, often with a gift in the form of an animal or human sacrifice. Fortunately, for most people today flowers and candy will do the trick. But then again, some Moms can be tough to appease.