A married couple, Megan and Greg, find themselves at a parenting crossroads when Megan lands her dream job and the couple has to figure out how to continue raising their two kids.
A widower and aeronautical engineer named Steven Douglas raises three sons with the help of his father-in-law, and later the boys' great-uncle. An adopted son, a stepdaughter, wives, and another generation of sons join the loving family in later seasons.
Thelma Harper and her spinster sister Fran open their home to Thelma's recently divorced son Vinton and his teenage son and daughter. It's quite an adjustment for everyone, especially the cranky, argumentative Thelma.