Your teenager is dating someone much older, how to handle this
There are bound to be friends your teenager has that you do not like, it is hardly surprising when you think of all your friends and how some of them dislike each other. It becomes more difficult as a parent to keep quiet when the person you dislike is your teenagers girlfriend or boyfriend and even harder if you think their partner is really unsuitable. One of the concerns of many parents is the influence their teenagers friends on how they behave and the person they date is likely to have the most impact on the teenagers view on life.
When that date is considerably older than the teenager most parents feel a twinge of alarm. Often, the teenager is aware of your potential disapproval and the relationship may have been kept secret for a while so that when you finally meet their date, your teenager is already quite serious about them.
There is an obvious attraction for a teenage girl in an older man; he probably has money, a car and access to a lifestyle that is far more exciting than that of most high school boys. Your daughter may be very grown up for her age and find her peers somewhat childish, so an older boyfriend is more appealing. As a parent you worry about this young man's expectations, particularly regarding the physical element to the relationship, but you may not be comfortable talking to your daughter about sex.
If your son is dating an older woman there are a lot of different reactions; a sense that as a mother your place has been usurped, or as a father, concern that the influence may be very powerful due to a certain kudos attached to a young man dating a more experienced female.
If your teenager's behavior changes as a result of this older partner, they stay out later, you suspect alcohol or they start to question your authority, then you cannot ignore this. An older person can introduce your teenager to experiences they are not ready for and you have a duty to ensure your child knows what they are getting into with this relationship. Either you, or someone close to the teenager, that they respect, have to have the conversation about sex and alcohol, or your teenager could be at risk.
The influence of an older person changes your relationship with your teenager; your opinion may become less important and your values less relevant. If your teenager is still under the age of 18 then technically they are considered a minor in most states and the age of sexual consent varies between 16 and 18 depending on the state they live in. If your teenager is at risk from this relationship, the law can sometimes support you, but beware of driving your child away through heavy handed action.