A person is a person. Refer to the **individual** as such. 

***Examples:***

1) If anybody asked you about the money, tell the **person** that it is in my bank account.

2) I felt that somebody was in the garden but I did not see **anyone**.

3)  Speaker 1: A friend of mine helped me a lot.

    Speaker 2: You should thank **that friend / buddy / comrade / confidant**.

4) Congratulations on your new baby! What's the **baby's / child's /  infant's** name?