In Laravel, storing values to a join table without defining Eloquent relationship

As part of the onboarding process for my Laravel app, a user can enter the ages of his or her children. A user can have many children, and so there needs to be a kids table that stores id, user_id (which references id on the users table), and kid_age. This seems like a basic one-to-many relationship—a user can have many children.

In a profile view elsewhere in the app, I have display back the ages of each child. However, that's the only point in the app where the kids make an appearance. It seems like overkill to create an entire kid model just to manage the parent to child relationship.

Is there a lighter-weight way to assign values to a join table? If so, how would I save data to that table without defining the relationship between two models?

via Chebli Mohamed