This is the adorable moment a toddler couldn't stop beaming as her loved ones sang "Happy Birthday."

Isla Mazlahn, one, celebrated her first birthday surrounded by family and friends and when the group began singing, the music-loving tot couldn't hide her joy.

Isla has been a fan of music since before she was born, often moving around in her mother's womb whenever a good tune played.

So it came as no surprise to her mum Abagayle Furchner, 23, that having a crowd sing "Happy Birthday" made her little girl so happy."

Abagayle, a stay-at-home mum from Stillwater, Minnesota, said: "It was such a joy to see her smile like that."

"I knew this moment would mean a lot to me as her mother, but I didn't expect for her to enjoy it so much."

"She really melted everyone's hearts."

Abagayle has played music for Isla since pregnancy and it's now part of their daily routine.

Isla regularly reacts with beaming smiles, dancing and head-bobbing whenever music plays.

Abagayle said: "I can remember holding my phone to my stomach when I was pregnant and feeling her move whenever I played something."

"I'm not a big TV fan, so a lot of the time we spend together we are listening to music."

"This video of everyone singing has now become her favourite thing to listen to."

"If I'm listening to it in another room, she will follow the sound and come find me so we can watch it together."