15-2: lo que es esta tarde: as far as this afternoon is concerned.
15-3: ha de tocar: must play. Cf. note había de conocer, p. 3, 4.
15-4: es mi día: it is my saint's day (which among Catholics is celebrated as a birthday).
15-5: papá abuelo: dear grandpa. Abuelo is often used in addressing an old man.
15-6: ¡Quita allá!: a phrase used to express emphatic dissent. Translate Not much!