[GRO] Milestone doesn't show up in one of the 2 sims

I have relationship socials (the both became best friends fine) for one Sim not producing but the other one is. If that is similar. I do play with mods and I might be isolated to this save, I just do not want to do the hassle of redoing the play to find out. I did read it is common issue, I just been trying to find an active bug report on it.

recently I had two sets of sims that got married. When they were engaged the greyed-out milestone for "get married" would show up for both men and women, however, when they actually got married, only the women would have the milestone for marriage, and the men wouldn't even have the greyed-out version. This remains the case with mods disabled as well. 

NB: I have tried looking for previous reports of this and found reports that I wanted to comment on, but the comments were locked hence why I am making a new report.

I've had the same issue for around a month or two now. It worked completely fine before.

Now couples fall in love, first kiss, get into a relationship and get engaged and then married - but only one (if any of them) get SOME of the milestones.

I've had sims getting married and then one of the sims not having any milestones at all related to it while the other had the above mentioned. I noticed when he got a bucket goal to get married. Say what? You already are!

I then noticed he is married if I check his info using the relationship panel, he is also married in the family tree (and cas when I check there), but he does not have the milestone (and bucket goal did not recognise it). 

Yesterday I had one sim have the option to throw a wedding on the phone, but when I selected it I could not continue because only he was selected and I could not add the partner. Even though they were already married so I should not have been able to get that far to begin with.

I also have had bucket goals on sims to renew vows, and then I need to select the other sim than the one I have selected to click on the arch to do it. Because that sim I had selected first is not married so I cannot renew it - even though they are!

Sims used to get appropriate milestones (I did have issues with best friends when one sim was an alien from the beginning, but other than that they worked). Now it is a gamble who gets what. 

95% of my married sims do not have the milestone for married, some not even engaged and some not in love or relationship etc, despite the fact that they did fall in love etc first. (I did not cheat and I don't play with mods or cc). It does make the relationship off as when you check the other sims profile (sometimes) in the relationship tab, the info there (except married for some reason) might not be complete. Like there is no "in love" etc. Just spouse and friend or even acquaintance, even though it is impossible to be married will a full green bar and just be that...

Yesterday I also had an issue where a sim couple had had another baby while I was not playing them (got a phone call in another household), but there was no milestone for it. Just for the other two ids where I had been there then they were "born". 

MIlestones used to correct itself when you added a previously unplayed sim to your household and they would get milestones such as married (and the required ones for that one (in love, engaged etc), child born x times for however many kids they had. 

Now you get nothing, or maybe one if you are "lucky". 

If sims get married in a save and have kids they should be in the milestones. If I later on add one of the couple (without the kids and the partner), there should be no married or had kids born milestones, because they do not exist in this save.
That is it. Not this weird half-assed thing that has happened. I don't know if this came as an issue with one of the latest updates or because I bought B&(n)H, but it is making me so frustrated. What is actually missing in the game code for the game to not realise sims to be married when they are everywhere else but in milestones (and sometimes bucket goals)?