The Eustachian tube connects the throat and the middle ear (the site of a typical  ear infection ) and allows air to travel between them and equalize the pressures. When the Eustachian tube is temporarily pinched off, pressure can build up in the middle ear.
Visitation is a matter of state law, but generally speaking, every state allows parents to exercise a reasonable amount of visitation with their children, which generally means enough time to establish and maintain a meaningful relationship.
1 A judge may limit visitation if a parent fails to establish a relationship with the child.  Addiction. When substance abuse causes a parent to use abusive language, drive while impaired, or mistreat the child, a court may restrict or even deny visitation.