US teen sent more than 10,000 birthday cards and gifts

Hallee Sorenson's 19th birthday celebrations are off to an amazing start. Photo / Facebook

Hallee Sorenson was devastated when no one turned up to her 18th birthday party last year.

The US teen, who has autism, spent her birthday waiting at a bowling alley to celebrate with her classmates, but no one showed up.

The heartbreaking photo from Sorenson's birthday last year. Photo / Facebook

This year, Sorenson's cousin took action to ensure her 19th birthday would not be like last year's.

Sharing a photo from Sorenson's party for one, Rebecca Guildford appealed to social media to "flood" her cousin's mailbox with birthday cards and gifts.

And people from all over the world have responded.

Today's cards and letters! Thank you!!!

Posted by Hallee's 21st Birthday on Monday, 13 June 2016

Postal officers in Bangor, Maine, have delivered more than 10,000 cards, letters and gifts to Sorenson's family home since the Facebook post went out on June 8.

This is Bangor, Maine's postmaster, Stephen; he's helping John unload all the mail for Hallee from all of you. 😳😊❤️ Again, your kindness and generosity is overwhelming. Thank you. 🌎❤️

Posted by Hallee's 21st Birthday on Monday, 13 June 2016

The gifts, which had to be transported in trucks due to the sheer volume, include a doll from a NASA employee and a parcel from a soldier based in Afghanistan.

How's that for a smile? YOU have all helped to put it there. 🌎❤️

Posted by Hallee's 21st Birthday on Monday, 13 June 2016

On a Facebook page that has been set up to share updates on Sorenson's birthday celebrations shows the teen thrilled with this year's gifts.

It's expected the generosity will keep coming at least until Sorenson's actual birthday, on July 2.