Living with mom and dad it is trending. That is, whether due to financial, health or other circumstances, young adults are moving back home after college and older adults are moving in with their children later in life, bringing multi-generational households to the forefront once again. This style of living, wherein two or more adult generations or the combination of grandparents, parents and grandchildren live together under one roof, has a long history. Whereas 19% of the U.S. population, or 60.6 million people, had such an arrangement in 2014, a 21% share of the population did so in 1950, according to data from the Pew Research Center. The more recent figure is up from the category low of 12% in 1980.