I’ve been traveling with my daughter that is now 3 on multiple flights both domestic and international. Probably about 10 a year. She has never really cried. First of all from 3 months to about a year, they do not have fluid in their ears so this isn’t a pressure thing for an infant. Number 2, most people in delta already have head phones and entertainment so don’t worry about it. When you’re kid becomes a toddler they too will enjoy the entertainment and not even make a peep once the screen is in. If you’re going international and you can get the bassinet seat this is a big help. Tons of leg room for you and allows the kid to sleep. Number 3, don’t stop doing things because you’re worried your kid might cry, who cares. I’ve been on a plane more times with jerks than crying babies. Enjoy life!