Millennials think a specific sound of their childhoods has disappeared. As soon as I heard it again on TikTok, I had to find out why.

Millennials think a specific sound of their childhoods has disappeared. As soon as I heard it again on TikTok, I had to find out why.

A woodpigeon call has gone viral online, sparking nostalgia for many.Getty/Alex WalkerA bird call has gone viral and taken people who grew up in the 2000s right back to their childhoods.I remember the same sound waking me up as a kid and soundtracking my teenage years.I asked an expert why the sound seems to have disappeared for so many.There's a specific sound that followed my generation through our collective childhoods, and many of us are won…