Bring a saucepan filled with 2 cups of water to boil and add some salt. Once at a boil, reduce the heat and boil the chicken breasts until they are done - about 25 minutes. Allow the chicken to cool in the broth and then remove them from the liquid. Reserve that chicken broth. Shred the chicken meat and put it aside.
Melt the butter in a saute pan and saute the garlic, celery, green pepper and onion until the veggies are limp, about 3 minutes. Set this aside.
Bring the reserved chicken broth to a boil. Then add the rice and sausage and bring it back to a boil. Add the tomatoes, the sauteed veggies, shredded chicken and sherry. Simmer this mixture for about 15 minutes.
Add the shrimp, oysters and crab. Cover and cook until the shrimp turn pink, about 5-8 minutes.
Check your seasoning and add salt and pepper to taste. Add some hot sauce if you'd like!