Two-year-old Sarah's parents are trying to get her to go to bed each night at 7:00. On the first three nights of this new regimen, Sarah cried for three hours before crying herself to sleep. On the fourth night, Sarah's parents relented and let her stay up until she fell asleep on her own, around 10:00 p. m. According to the partial reinforcement effect, what will happen to Sarah's crying behavior at bedtime now?