She needs my kidney!!?

I'm 14 and one of 7. I am the fourth child. I am very connected to my three younger siblings who are triplets.(age5) Two, amy and damion have cerable palsy and hailey has kidney failure. I am the only imeadiate family who is a match and can give her a kidney. Now I would however last year I got over my 3rd year of leukimia. I am now in remission. Is it safe to give her my kidney? P.s no immideate family is a match and the doctor said it is better to come from immidate family if possible. I just wanna no if it's safe. Thankyou xxx