Martina McBride's charity, Team Martina, gets a lot of support -- especially from dedicated McBride fans who also have a heart of gold. One huge McBride fan (and Team Martina member) got the surprise of a lifetime during a recent soundcheck.

When the 'I'm Gonna Love You Through It' singer was doing a routine soundcheck of 'Anyway,' she invited 16-year-old blind singer Madie Hendrix to join her -- the two made the song a duet. This was McBride's way of saying "Thank you" to the teenager who has been helping with the charity.

With Hendrick's help and 44 fan volunteers, Team Martina raised over $33,000 for the Covenant House in Guatemala. This money in particular will go towards helping children in Guatemala get new musical instruments to help their dreams come true, too. The fan volunteers spanned over 20 states and they all met in Huntsville to raise the money.

"I'm still in shock, I don't know what to say," Hendrix says in the above video for WAAY-TV. She was in disbelief that McBride was talking to her. "At first, I was like 'No, no, no she's talking about somebody else. There's another Madie in here that I don't know.'"

McBride seemed just as happy with the surprise as her fan did. "It was great for me to have Madie on stage," she says. "Anytime I can see a young person that loves to sing it takes me back to when I was a kid and loved to sing."

She was also really proud of her fans and Team Martina members. "We're going to make a difference with this. It feels good," McBride says with a smile.