Bridesmaids belt out surprise medley at sister's wedding

It’s a great effort, but warning they REALLY can’t sing.

Kelsey and Maddie Hallerman delivered a performance to remember at their sister Caitlin’s wedding in Lake Tahoe, California.

The co-maids of honour wanted to do something special for their sister’s wedding to her new husband Johnny Weaver, so they took a medley of popular songs and customised the lyrics to fit the occasion.