I hadn't heard this but I'd imagine it relates to a strong canary yellow- which you are unlikely to use anyway!
In DS's room, we wanted unisex colours, so we have 2 walls painted in a soft yellow (Dulux 'Daisy Mews'). The other 2 walls are painted in a soft mint green (Dulux 'Pixie Mint') in a half tint. I have heard that green is supposed to be a calming colour. Its my favorite room in the house- very warm and friendly. I love it and DS loves his room too.
And nope- he doesn't cry all day!!! He always wakes up happy and babbles to himself.
Sounds a bit silly to me......

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