In Spring it was not possible to have a vassal or a vassals wife as a mistress, is this still the case?

Still working on this? I got some ideas.

leave any suggestions here, if i have time to work on it again I'll consider adding it in :)

I think some of these suggestions are more for the wider lover status but consider:
1 - Different bonuses if the paramour is married vs unmarried.
2 - A big boost in their feelings towards you if you legitimize her children.
3 - A higher chance they can become lovers with YOUR lovers.
4 - Some events in regards to sex especially if you are up there in age. Similar to CK2.

Other question, would you be okay if I made a spin off of this mod if I gave you full credit?

Inspired by your mod, I’m working on a Paramour Court Position Mod myself.
There are some obvious similarities, as using the term Paramour and a Scandalous Opinion Modifier. And without your mod, I would have never spent a thought about paramour or female liege becoming pregnant (I’m still working on handling that matter).
But in detail, there are great differences. For example, the paramour gets a trait, reflecting how scandalous the relation to their liege is seen by their faith, and the liege gets a character modifier, doing the same. Every spouse and soulmate of liege and paramour also receives an opinion modifier towards both of them, depending on how scandalous that relation is. On top, liege an paramour get a character modifier, depicting the paramour’s aptitude as seen by every courtier or guest.
If you don’t have any objections, I will publish it as my own work and name you as my source of inspiration.

Go ahead, I will probably update the mod again when I'm interested in playing CK3 again which may not be for a few months but until then I do feel bad for keeping this mod un-updated, considering how time consuming modding is. You have my blessing to create a similar mod for sure, I'm sure people will appreciate it

Thanks a lot. And you're totaly right: Modding is very time consuming.

Found a bug. when any woman gets pregnant she stays pregnant forever and you aren't notified or able to name your children when they're born. They can get pregnant again, and if you mouse over the trait and watch the month count go up until it hits 8/9 and then resets to one and a new child appears.

Thanks minro, is this for any random woman in the game or your spouse etc?

I've just fixed this bug, thanks for the report!

Regarding the "I am the Liege" bug, it seems to be triggering as a direct result of going to war. I also don't think it triggered before I formed the kingdom of Italy as Matilda (which makes sense, the role is tied to being a monarch). It might also be tied to having a lover, as I had that before I formed the kingdom.

My male successor finally got a Mistress and when they had a kid, the text for it was replaced with the name of a .desc file. This makes me assume this is an outright broken version of the mod. Unfortunately, I have had no luck so far trying to force Steam to actually redownload it.

thanks for the extra details, I'll try to reproduce it like that. There was an earlier comment with a similar issue regarding the event firing when acquiring new titles so it might be related somehow

The localization file mistress_events_l_english.yml is incomplete.
It abruptly ends on line 86 with "mistress_birth.2001.t:0 "The Product Of Love""
And nothing more. It feels like there should be say 2 more lines or more if there are other events not in the localization file.

Hey Cavve, going off memory I reused some existing localisation (basically the same event text) in those events and only changed the title to make sure the event was actually firing because I'm lazy. When the event fires is the event body not appearing?