Double-Jointed Elbows? Wake up your shoulders!
"I was born with double jointed elbows."
No, you weren't (unless you have a connective tissue disorder - which is rare).
Because of the modern environment in which you were born, your body didn't develop as per its evolutionary design, your shoulders locked up and your elbows and wrists ended up working too hard and now don't work functionally aka they hyperextend.
The more the elbows and wrists get used to twisting and turning in ways they shouldn't (compensation), the more the shoulders lock up. There's no stimulus for the shoulders to mobilise properly, so why would they?
It becomes a spiral of dysfunctional movement where the person involved never realises what functional shoulder movement actually looks/feels like and then starts blaming their age or sport when they start developing things like Golfer's or Tennis Elbow, or Carpal Tunnel Syndrome. It's because their shoulders have remain locked up for x amount of years and the elbows and wrists work too hard.
Opening up your shoulders and short-circuiting your normal compensations takes a) knowledge of how functional shoulder movement looks/feels so you know what you're aiming for and b) hard work.
I wouldn't give someone with hyper-mobile elbows anything where they are having to load weight through their straight arms (as they will just buckle and hyperextend with the weight aka compensate), it's not conducive to progress. Someone with double jointed elbows needs to re-learn functional shoulder movement and build strength into elbow flexion. This will only happen when their body isn't being challenged too aggressively. Doing handstands or chatarangas or anything like this is only going to cause distress at the elbow and wrist joint, until the shoulders can move better.
I hope you find these 6 moves helpful and good luck on your journey to correct those elbows!