I get up at 7 am every day. But my husband gets up at 5 am to go to work and not be late. At 7:30 am he returns home to get breakfast, so I cook breakfast for us once I am awake.
Sentence 2: The predicate (main verb) is "gets up", which is third person singular. Who gets up? ="husband" is a noun used as a subject, and it is third person singular. The subject and verb in this sentence agree.
Sentence 3: The first predicate is "returns", which is also third person singular. Who gets up? = "he" is a pronoun used as a subject, and it is third person singular masculine. Its antecedent is the noun "husband" in sentence 2, which is also third person singular. Therefore, the pronoun and its antecedent agree.