Please don't list this on a work's page as a trope. Examples can go on the work's YMMV tab.
Tear Jerker: Independence Day
Patricia: Is Mommy sleeping now ?
Whitmore: Yeah. Mommy's sleeping.
The fact that she immediately crawls into his arms and hugs him tells you that even at all of six years old, she knows exactly what he really means.
The look on Hiller's face when he finds out that the air base where his fiancee and stepson were headed has been destroyed. They're alive, but he doesn't know that, and they have a similar reaction when they think he's been killed.
The scene where Russel's teenage son overhears his dad's last message..... and not being able to say goodbye after all those times of thinking his dad was nothing but a loser.
A meta example - this film was the swan song for an era. It was pretty much the last big-budget special-effects movie to rely almost entirely on practical effects and models, rather than CGI.