Brian shows Catherine a seashell. He says he found it when he was in Boston. Brian and the other children never visited the beach. He could not have found the seashell.
The town cemetery has more and more guests, but never grows in size.
Dr. Quinn has issues with Sully kissing Catherine. Dr. Quinn is being a hypocrite. She was going to marry Dr. Burk a few weeks earlier.
Catherine is wrapped in a multi-colored blanket. A multi-colored blanket in the late 1800s is very expensive and it is unlikely that Dr. Quinn would have one.
Jake was able to hold onto a tin cup filled with boiling hot coffee with his bare hands.
It is not clear how Sully found an Indian dress in one-day. The dress takes months to make when starting from scratch.
Catherine shows up in town with her hair a mess. She had been living with Indians. All the Indians on the series had neat hair. It does not make sense for Catherine to have messy and unkempt hair.