Researching the possibility of an adoption 70 years ago

[Usernamesarenotmyforte]

Apologies in advance if this gets a little long and rambling.
One of my parents has had a suspicion for several decades now that they may have been adopted. In the 90s they tried to find the official record of their birth as they only have a short birth certificate and they were unable to find anything under their dob and (supposed) place of birth. It then transpired that their birth had not been registered within 42 days and that it was in fact closer to 3 months (sorry this bit isn’t clearer, it was described to me from memory).
I’ve just had a nose using find my past and easily found all other family members, my husband and in laws etc. I’ve even tried slightly varying combinations of what I put in and can still find the records. Cannot find them for this parent, the only other person this is the same for is our friend who is adopted (and knows this). I should add that we can find other records for my dad such as marriage etc.
At the moment my grandmother is the only surviving parent and also only one of her generation in the family. She is in her late 90s and has dementia. For many reasons it feels horrifically inappropriate to even try to ask her. There’s the added complication that part of why my dad even had these concerns was that she was not the best of mothers (emotionally manipulative and also hit him when he was a child). It’s all a bit of a mess really.
So my question is, if we wanted to find out, where on earth would we even start? Any suggestions very welcome. Thank you.

Do you still have the short copy of the birth certificate? That should make accessing the full transcript much easier.

Whoops, pressed enter too soon...

www.gov.uk/order-copy-birth-death-marriage-certificate

If you're in England/Wales then you can use this service to order up a full copy of a birth certificate which may give you more information such as parents' names or place of birth.

The other idea which immediately springs to mind is a DNA test through one of the sites like Ancestry. If your dad has siblings who would be prepared to test too, or even more distant relatives like cousins, then that might help. You can look up the percentage of expected shared DNA and then compare results - for example you could expect a sibling to share 50% of your DNA. If your dad tested, and so did a brother/sister, and the results were way lower than that. you know something's not quite right. It may also be that your Dad matches with someone else who has tested who he doesn't know, which could give avenues to explore.

If your Dad does suspect he was adopted, then he could request a copy of adoption records. This is quite a lengthy process, which involves counselling.

www.gov.uk/adoption-records

Of course if he was "adopted" but not formally, or was the product of an affair or something, that might not be recorded.

I'm sure you're aware but this could open up a whole can of worms for your Dad in terms of dragging up stuff from his childhood or questioning his entire identity. He'll need a lot of support, and should think long and hard about whether this is something he really wants to get to the bottom of, or if on balance, he'd be happier not knowing.

Your father, if adopted would have a primary birth certificate that is totally different from the shortened version

Your father and only your father can apply directly to the GRO for a copy of his original birth certificate

Usually anyone can search and apply for birth certificates but adoption changes these things and basically your dad if adopted will have two, one original and one adopted

You won’t find them on the normal GRO indexes as these documents are not accessible

Have a read of the two links below and hopefully it explains how you go about this research with your father ( as it’s your fathers data it is protected by data protection)

www.gov.uk/adoption-records/the-adoption-contact-register

www.whodoyouthinkyouaremagazine.com/tutorials/adoption/

Thanks both, at the moment I don’t think it’s something he would like to look into- it’s more the reassurance that if he does decide he wants to in the future it can be done even if his mother has passed away. He has no siblings (that we know of) but there are cousins on the one side- however, that’s the side we all suspect he may actually be related to! To be honest, I’m not sure any of us are ready to open this can of worms.

Would he do an Ancestry DNA test ?
It might be very useful

Daft question maybe. Have you looked for his birth under his mothers maiden surname? I have an ancestor who we think managed to register the same child twice (and got married between the registrations and so the child appeared under 2 surnames to hide illegitimacy). All conveniently "hidden" by a house move and disruption caused during WW1

Has he checked the date that his parents married? Does he have siblings?

Sorry, just re-read and saw he has no known siblings.

Parents definitely married. I did look under his mother’s maiden name but they were married in 1945 and he was born 6 years later so it’s doubtful he would have been registered under a maiden name. One of his paternal cousins is doing a lot of digging into family history, including dna stuff so it’s possible that may throw stuff up.

Write to the office that does lengthened birth certificates, explain you only have a shortened birth certificate. They will ask a few simple questions. One of which will give them more info than you can imagine. Good luck. I can't give you the question on here. But pls do what they say.