Kathryn's 5-year-old developed a strong interest in spelling once she learned to spell STOP. After that, she tried to figure out her own words. From the back seat of the car she'd ask, "Mom, what does FGRPL spell?"
"Nothing," Kathryn said.
Sitting at breakfast she'd suddenly ask, "Mom, what does DOEB spell?"
"Nothing," Kathryn answered.
This went on for several weeks. Then one afternoon as they sat coloring in her room she asked, "Mom, what does LMDZ spell?"
Kathryn smiled at her and said, "Nothing, sweetheart."
The 5-year-old carefully set down her crayon, sighed and said, "Boy, there sure are a lot of ways to spell 'nothing'!"
While watching the tv show "Sisters", my then 5 year old daughter was having a hard time understanding how one sister was expecting a baby but the baby belonged to a different sister.
After explaining to her that the egg from one sister was placed inside the body of the expectant sister, she then asked, "Does the egg have shells?"