New Jersey bartender Christina Summitt planned to sell her car to pay for her dog's expensive surgery until she received a $1,000 tip recently.

After chatting with a couple in the bar about her volunteer work with animals and her 3-year-old dog's health issues, Summit found that the couple had left her quite the tip on an $80 bill.

Thinking it was a mistake, she ran after them to return the money, but the couple, who asked to remain anonymous, told her not to take it and pay for her dog's surgery.

Summit's dog, Tucker, is now recovering after an unusual mass — which turned out to be a tennis ball — was removed from his stomach.

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