To dream of getting a vaccination represents a wish to become resistant to something that has taken hold of you. It may also reflect a wish to immunize yourself from dangerous situations or bad choices that have become a problem. Doing whatever it takes to not be “infected” by a bad situation or bad choice that has gotten out of hand.
To dream of your father getting an vaccination may reflect a wish to immunize yourself from a bad decision. Realizing that you need to take permanent action against a mistake or careless choice you made so it doesn’t get worse. It may also reflect your wish to remove yourself from any responsibility for your choices or avoid blame.
To dream of your mother getting a vaccination represents your wish to immunize or permanently isolate yourself from making future mistakes or face future consequences. Making a serious choice now that will protect you from making further bad choices or problems down the road.