A seven-week old baby boy has been previously diagnosed with hearing impairment, which means he is suffering from moderate to severe hearing loss in both ears.

But on one special day, baby Lachlan was given his first hearing aid and his reaction to the sound of his parents' voice was priceless.

"When they turned the headphones on and Lachlan smiled and his face lit up, it was the most magical thing I'd ever seen in my life," his mother, Michelle, told the Daily Mail.

Check out the adorable baby's reaction to sound! It's absolutely charming!