From Time Magazine we get some interesting terms for the opposite phenomenon. Here is one:
“Failed Fledglings”
Leave it to the United Kingdom to come up with this humdinger. According to a survey published last summer, some three million parents over age 50 had grown children living at home—a category the poll called “failed fledglings.” A corresponding 16-page “Parent Motivators” booklet was published in order to help parents cope with adult kids back in the nest, and the contents reportedly included “tips about how to get rid of children who you would prefer to have moved out.”
Here is a link to the article https://time.com/72304/adults-parents-insults/