All of the kids younger than Harley were "oops babies."
That's the only logical reason for there to be such a large age gap between Harley and the twins, when all of the older kids have a year or less between their births.After Daphne, either Tom had a vasectomy or Suzy had her tubes tied.
This is why there are no children younger than Daphne.Suzy was a nervous virgin on the night of her honeymoon.
When Suzy and Harley were supervising Rachel's driving habits in "Stuck Without a Ride," her response for Harley's for her quiz was to "close my eyes and think of rainbows," which sounds like something many mothers tell often used to tell their presumably virgin daughters when they marry them off. Daphne grows up and changes her name to Rosa and moves to Brooklyn
Daphne always wanted to be a cop, and she is a bit unsettling. Suzy is Marcy from Cabin Fever, Ethan is her lovechild with Paul, and Rachel and Georgie are Tom's children from a previous relationship
Marcynote somehow got away from the dog at the end of Cabin Fever (you never actually see her die, or her dead body). She was nursed back to health by someone and survived the disease. Then she moved across the country, changed her name to Suzy and fell in love with Tom, a single father with 2 baby daughters, while she was pregnant. Cabin Fever's Paul
note and Ethan have some serious father-son resemblance going on.