COULD IT BE HIS BABY?

My cousin went to our country on July 31 and came back on August 14, he has a girlfriend over there he met on FB. She calls him lask week and tell him that she's pregnant. I tell him that its completely impossible that the baby could be his, the only thing he has to do is to ask her the last time she had her period on July, now she refuse to tell him pretending my cousin is offending her. Do you guys think it could be his?

The reason I said impossible is because month before my cousin went there, she posted on fb that she's pregnant, my cousin even liked her post, maybe he thought she was joking.

I know the baby could be his, but why she refuses to tell him the last time she had her period? If she has nothing to hide just tell him