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Okay, let's say Dede's being "Terri" at the gym with the baby in the gym daycare, so the real Terri can have tryst. The plan is that Dede's already in Terri's neighborhood working, so she'll meet Terri and use Terri's truck (carseat's in it) and take the baby to the gym while Terri has adult time. At least, this is what Dede thinks. She won't speak of it back at work either because she's Terri's BFF. Dede brings the baby back as scheduled - or Terri meets her at the gym as scheduled; they change cars.
Compliments of Dede & Dede's vehicle, Terri gets another 160 minutes to take care of the business at hand.
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Terri either has 90 minutes, or with help, 90 minutes plus 160 minutes to dispose of Kyron.
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