bipolar who does it affect

How does being on SSI as a child affect the child’s future opportunities?
I know of parents who have tried to get their kids on SSI who have no known impairments to daily functioning.
I’ve heard if you’re ever placed on SSI for bipolar you can’t work in the armed forces, any law enforcement job, high-stress government job, or own a gun. I’ve also heard similar problems with ADHD. Do you know if any of it is true? (I’m talking about documented and treated Biploar D/O or ADD/ ADHD combined or NOS.)
What are the actual limitations to a child’s future if the parent puts the child on SSI somehow?
Under the current structure they will live in poverty!
Self-Injury: It can affect anyone. *WARNING: MAY TRIGGER*