Unofficial Skyrim Special Edition Patch

We'll need a bit more than that to go on since his kids have several lines they can speak.

Sorry. Nelkir, Frothar and Dagny won't say their normal dialogue, meaning dialogue like "One of the new servants? Remember that I like my meat rare." or "Another wanderer, here to lick my father's boots. Good job." when you speak to them, the subtitles for such dialogue will appear briefly but then disappear. The conversation between Frothar and Danny about the dress won't play/happen as well. The only dialogue that occurs properly is the generic Npc dialogue that happens once it has run out of lines, the "Hmm?", "Need something?" and "Yes?".

OK, that's what I figured. Those lines have been disabled by Bethesda in the game's master file. They were placed to run in the Whispering Door quest but they cut them out because they were supposed to be generic dialogue.

USSEP transferred those lines over to the general Whiterun dialogue, but because of how voice resources work those files had to be given different filenames which then made it impossible to fix on Playstation.