White noise: Whale sounds

My two children are neurodivergent but as babies the only sound that calmed them to sleep was whale sounds. They were a feature on the baby monitor (amongst many others!) They listen to Yoto stories every night but one child in particular remains hyper active as I’ve tried all the white noise sounds. The more timid child of the two likes the crackling fire to go to sleep. So was thinking a card with whale sounds to go to sleep to?

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