PSA: If you are hoping to catch Mom or Julia in a certain state, like drunk or coffee Mom in the dining room, Mom tanning close to the living room door or across the pool, or Julia crying or not in the living room, and you find them in the unwanted state, leave and come back again. It's RNG which state they'll be in, and as long as you don't interact, time won't pass.
That works with Kelly at the shop (at attention, or back to the register), and to a less consistent degree with Emma in the back yard. Unfortunately with Emma, time will still pass if you leave.