Help Sebastian Live a Couple more Years!!

My dear & beautiful dog has been diagnosed with having an abdominal mass that needs to be surgically removed. The expense for that is about $1500 & hoping that it isnt malignant & they dont encounter any other problems. Because of this i need to be taking him to get evaluations on his liver & his anemia. He also has hypothyroidism which i am treating him for.All funds will be used for the surgery & monthly evaluations needed until he recuperates.  Ive been given a window of about 2 to 3 months to make a decesion on what im going to do. In the meantime his mass will be growing & interfering with his organs. My doggie has been a big emotional support to me since I'm disabled & live in chronic back pain 24/7.  I dont know what i would have done if i didnt have him. He brings sunshine to my life everyday. There's nothing like the love u receive from your dog. I got my dog when my world was falling apart & i thought i was going to go crazy. He helped me so much & even though hes old, going to be 12 on the 3rd of July, I would like to have at least 3 more years from him. Im not ready to let him go. So plz, whatever support i can receive i would be so grateful!!! I don't want to have to euthanize my dog if i don't need to.