To think DH is losing the plot re: DS’s new girlfriend??

Willing to bet he is a racist, but given that the OP says she lives in a majority white area it has never been an overt issue. Now he has seen his son with a dual heriage girl he hates the idea and just like any racist he assumes that she or her family must be involved in some shadowy stuff. Her parents will surely go beserk if they even get wind that he has been contemplating this let alone doing it

Tell your husband that if he doesn't stop gassing on about stalking a child via a PI for absolutely no relevant reason, you're going to call his GP and the local MH crisis line on his behalf. As he's clearly suffering from paranoid delusion, possibly psychosis.

What an absolute weirdo.

And if you think it's because she's half not white then you should divorce the racist prick..

The poor girl!

If he thought he was her dad and wanted to hide it, he’d hardly be pushing for a private investigator with OP’s full knowledge. That doesn’t make sense. Some of you have read too many twisty ‘family secret’ thrillers.

Surely it’s more likely he either knows her from somewhere dodgy or mistakenly thinks he does — or his mental health is out of whack in some broader way, and he’s fixating on this young girl. Maybe he’s been reading a lot of toxic machismo BS online.

Could he be spying on your sons phone?

Adding to the other theories:

1. Is this your DS's first proper girlfriend (as in sexual partner) & your DH is a bit prim & proper?

2. Did something bad happen to your DH earlier in life & the GF has somehow triggered him (something to do with her name, looks, general background) e.g. was your DH attacked, a drug dealer or involved in any crime & the girl's family were involved? Or has your DH committed a crime against her family?

3. I don't know what your DH's job is but if he's in the police, social services, security services, military, medical services does he know something that would get him into trouble if he directly told you because of the confidentiality/ethics of his profession? (This does happen)

4. Is your DH a true crime fanatic & he's thinking the GF is a child of a major criminal or a notorious murderer?

5. Does your DH have a secret life - is he a secret drug dealer & has sold drugs to her family?

I really think you need to have it out with him.
I hope it's scenario 1 or even scenario 4 although that is a bit bonkers!

I hope your DH isn't in the throes of a mental breakdown or up to no good

This will sound mad (but not madder that hiring the PI in the first place) but maybe he will get them to collect something with her DNA to compare to his. Then he’ll also want the PI to find something incriminating to break them up if he is her dad. Again, I know that sounds mad!

Has he expressed racist views throughout your marriage? Why would he be okay the first couple of times meeting her and then suddenly change?

It’s almost like something has happened?
maybe it is OnlyFans although you would need to be 18 and surely verify age?

Bizarre!
Lets say worse case scenario she is cheating, your DS must love and learn the hard way like the rest of us. It’s called life experience and regardless of how he found out if she was cheating, it’s going to hurt him either way.

I think all the wild ideas are probably less likely than a dad realising his son is growing up and freaking out as he has no control and trying to find some control (in a totally bonkers way!). I’d get him to go to counselling.

But then how’s a PI going to help?

Yup. Oh dear. I couldn’t live with this.

I’m sorry OP

Your spidy senses are going off for a reason.

Don’t ignore them.

I don’t know what it is but I’d be checking his phone.

So true. I think it must be related to something pervy he’s doing because this is a weird reaction. Most people would say “no I don’t think so” or assume you meant at work/local pub/shop etc.

Did he date her mother?

This is so weird it’s actually led me to question could your husband be her father?

That’s absolutely bizarre. Definitely not normal behaviour!

he wants to what? wtf is he on

He does sound unwell.

Nah. I think OP has been married to him long enough to know whether she’s married to a racist. It’s not something he would be able to hide from her for so long. Just not possible. More likely to be snobbery in relation to what her family might be like. He knows which town she’s from, so will know if she’s from a nice area, which I’m guessing she isn’t. Hiring a PI if it’s just a racist thing would be irrelevant, as her race is there - doesn’t need investigation. He wants to know if her family match his own as far as class goes.

God I hope her parents don’t let her stay!!!

If he suspects she’s related to him then getting a PI involved isn’t going to help him, surely he’d be trying to get rid of her not let you find out more?

But if it is racism why hasn’t he objected before?

The Op says her son had been seeing the girl for a ‘few weeks’ , that she’s been in their house ‘they’ve been spending a lot of time here anyway’- it seems to be the request for her to stay over (and thus potentially sex?) that precipitated the bizarre PI request.

If it was racism what would hiring a PI achieve? Is he really assuming that she or her family are criminals based on her heritage?

if it’s onlyfans that would make more sense as he would be hoping the detective would discover that, but that’s now going to be blatantly obvious if the PI “discovers” that.

its all very bizarre and I don’t think my relationship could survive either option ☹️

Perhaps he knew the girls mother in the past ?

He has a witch hunter gene and the power to sense magic (although he doesn’t know this) and his unexplained dislike of this girl is because she’s secretly a witch 😆. (A plot from Sabrina the Teenage Witch back in the day).

I agree it’s odd behaviour but then again the protective instinct of parents can result in them thinking a boyfriend/girlfriend is a bad egg and isn’t right for their child. It is perhaps less common for a father to be this way about a son’s girlfriend but fathers thinking a daughter’s boyfriend is a wrong ‘un isn’t an uncommon scenario.
DH thinking about hiring Inch High Private Eye though? OTT.
Perhaps there is mileage in him having fathered another child and he’s convinced there’s a possibility the girlfriend is his daughter.