In addition to her husband, Brendan McLoughlin, Miranda Lambert has 20 important Valentines this year: They're 20 pet rescue shelters across the U.S., and the singer's MuttNation Foundation is celebrating each with a $1000 grant.

In total, the country star is donating $20,000 to grant recipients in states like Ohio, Montana, California, Tennessee and many more. It's the latest in a series of MuttNation initiatives to offer support to shelter pets and those caring for them, which has been a cause near and dear to Lambert's heart since she began volunteering at animal shelters as a teen.

"Shelter pets — especially the ones that are hardest to get adopted and the people who care for them have always had my heart," Lambert explains. "Valentine's Day gives me one more chance to show just how special they all are to me."

Founded by the singer and her mom, Bev Lambert, in 2009, MuttNation is a donation-support nonprofit aiming to improve the lives of shelter pets through promoting their adoption, raising spay & neuter initiatives and providing education and awareness-raising tools to the general public about the plight of animals in shelters. Lambert has campaigned especially fiercely on behalf of senior animals, animals with special needs and other shelter pets that face increased challenges along the road to finding their forever homes.

The singer celebrated her four-legged valentines on social media on Monday (Feb. 14), introducing followers to her pint-sized, nearly-15-year-old dog Delta Dawn, whom she found at an Oklahoma Sonic. Lambert shared a little bit of Delta Dawn's story and also invited fans to go to her website and take a quiz to determine what kind of dog is the best fit for them.

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