He can legally date a 1-month-old baby if the babys parents are ok with it. A person becomes an adult at the age of majority, which In most states is 18.

Is dating a 13 year old at 18 wrong?

It is not illegal for a 18-year-old to have a social relationship with a 13-year-old of the opposite sex, it is statutory rape however if there is any sexual activity between the two parties.