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As the Doctor has said many times, he can't change established events in his own timeline. The Eleventh Doctor was angry with Amy Pond because she read to him the passage in River's book about River getting her wrist broken, establishing that event in the Doctor's timeline & thus preventing him from finding a way to free River from the grip of a Weeping Angel without her wrist getting broken ("The Angels Take Manhattan"). The Doctor personally witnessed River's death ("Forest of the Dead"), so that too is an established event in his timeline & he cannot prevent it.

"Father's Day" showed the dangers of changing an established event in one's own timeline; that was what Rose did when she prevented her father's death. There is (sometimes) some "wiggle room", if what's established is in fact the appearance of an event, such as the seeming destruction of Gallifrey at the end of the Last Great Time War. The combined action of thirteen incarnations of the Doctor saved Gallifrey but preserved the appearance of its destruction ("The Day of the Doctor").