Daisy was like that until about 1-1/2 years. She saw an injured duck in the middle of a pond and she swam ... a LONG ways! The duck got away
She's still very cautious in the water. She will swim if something motivates her enough but she really does prefer to have her feet touching bottom.
One time I threw a fish back into the river, thinking my dog wouldn't go after it. Haha ... OMG, before I knew it she was in the middle of the river going downstream. Gave me a heart attack but man, this girl can really swim!
Your boy will surprise you one day too, don't lose faith. Just be careful with the fish

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