I turned 66 this month. My wife and I have a 24 year old disabled son with Down Syndrome who currently receives SSI. Our plan was for me to file a restricted benefit claim for spousal benefits and allow my benefit to grow until age 70. My wife will claim her full benefit in August 2018. Can my son access 50% of my benefit with my restricted benefit claim. This would almost double and replace what he currently receives in SSI. If not I assume he could claim based on my wife's August claim but then we would be subject to the family limit. Thanks in advance for your help. We could never have negotiated the system without your great book.
No. You'd have to be drawing on your own record in order for your son to potentially qualify for disabled adult child's (DAC) benefits on your account. If you follow your plan as described above, your son could potentially qualify for DAC benefits on his mother's record when she files and he could later file for DAC benefits on your record when you switch to your own account at age 70. He could only draw on the higher record, though, not both.
And you're correct that if both you and your son draw benefits on your wife's account the family maximum benefit (FMB) on her record will limit the amount that each of you could be paid. Your plan may well be your best option, but you should strongly consider using our maximization software to explore and compare your other options in order to make sure that your choosing the best possible strategy.