@lanlyn I used NRAAS Tempest mod and eventually managed to change the temperature range for Spring so snow can't happen. I also went into game options and turned off rain and hail. I want some sunny days in this challenge.
The Perfect Genetics Challenge Generation 1 Episode 21 is now up on YouTube
https://youtu.be/vE0_qAgDf5I
The main events this episode include Cindy ages up to child, Petal completes her toddler training, the house gets some extra rooms, pets join the household and the three boys and Don go on a festival egg hunt at the Spring Festival. I finally seem to get the weather under control.