Luna Needs Your Help

We adopted Luna a year and a half ago. She had given birth to 8 puppies a few months earlier and we just knew that she would fit perfect with our baby and our family....and she did. Our little boy loves her and she loves him right back! She is the most loving, maternal, sweet dog! She whines when my son leaves the house...she's so protective in the sweetest way.  She is still young, she will only be 4 in December.  Recently, Luna started losing weight. We have been taking her into the vet for the last couple months trying to figure out what is wrong. We went through parasite treatments to anti-inflammatory treatments to changing her food and more! We decided to take her in to get a second opinion, today. Well, the news broke our hearts. She has a rapid growing tumor growing in her abdomen (close or on the spleen). We need to do more x-rays and ultrasounds to determine exactly where it's located and if she can survive surgery. Surgery will cost at least $2,000 on top of our already incurred costs. We don't have much time. If she doesn't get this removed, she can rupture her spleen and bleed internally. Please help us do everything possible for our sweet girl. Please...