Possesive and Pronoun

[gmatNooB8787]

It is mentioned in Mgmat and other places that a pronoun must strictly have an antecedent or the sentence is incorrect.

However there is one statement in Mgmat Flashcard that i found, and i think this statement is incorrect.
Can anyone please confirm?

Statement:
 
Mr. Vega's mother noticed that a button was 
falling off his coat, so the coat was fixed by 
her. 
 

here "his" does not have an antecedent. Vega's is a possesive qualifying mother, hence this statement should be wrong.

[vk_vinayak]

The sentence is passive and awkward.

The antecedent of "his' is "Mr. Vega's".

"Mr. Vega's mother" is not possessive, while "Mr.Vega's" is.

'his' agrees with 'Mr.Vega's' and 'her' agrees with 'mother'. (Remember, 'her' can be used both as a possessive pronoun, as is her car, and objective pronoun, as in to her)

[bubbliiiiiiii]

 
Mr. Vega's mother noticed that a button was 
falling off his coat, so the coat was fixed by 
her. 
 

here "his" does not have an antecedent. Vega's is a possesive qualifying mother, hence this statement should be wrong.

His is an possessive adjective. Since his is used as an adjective here (describing the noun coat) I find this statement to be OK.

Hope this answers your query.