Counting Sheep - In many cultures, the act of counting sheep is used when someone cannot go to sleep.
The idea of associating counting sheep with the brand, conotates that the products have the same quality as the act of counting sheep. In other words, the products are relaxing and contribute to easy sleeping.
The hues of blue are soothing and conotate clear thoughts, relaxion, peace which in the end are all brought by healthy sleep.