Gina.......if I had the broken brick problem ......I think I would use some JB WELD to glue the face back on the brick.........Does it still fit?
JB is a steel-filled epoxy that has a strong, waterproof bond..........It's dark grey in color so it comes close to matching cement grout......
Two tubes......squeeze out 2-inches of each.....mix throughly(wood stick)......apply to both surfaces.........place the brick in position.......Clean-up any squeezout and clean the finish surface with alcohol to remove any smudges..........Prop in place accurately until cured.....several hours/cure overnight........catch any "drips" while the material is still plastic.......it's very hard when cured.............