Yeah... I was a bit disappointed how poorly that scene comes out.
It wouldn't even have needed who knows what, just a couple more dialogue lines would've made it perfectly fine, but that way it turns out pretty weak and not even a single mention of the fact Gladio's father died as well.
I'm not saying they should've dedicated like 2 minutes to mourn Gladio's dad death, a single dialogue line would've been fine, like
someone: Your father died too Gladio...
Gladiolus: No time to mourn, he knew what he was doing, I'm sure he died proud, We need to think of what to do next, to protect Noctis, the future king.
Just making a silly example.
The fact it doesn't even remotely get mentioned is quite, I dunno, I found it a poor choice in terms of the emotional potential that scene had.