I have two kids that receive benefits from disability from there father. My oldest will be 18 next year. Will her younger sister receive her benefits?

Hi. Assuming that a) your 2 children are the only people getting benefits from their father's account, and b) neither of your children receive any other Social Security benefits, and c) their father is receiving Social Security disability (SSDI) benefits and not Social Security retirement benefits, then yes your younger daughter's benefit rate should increase by the amount of your older child's benefit when the older child's benefit eligibility terminates.

The family maximum benefit (FMB) that can be paid on the record of a worker who receives SSDI benefits range from 100% to 150% of the worker's primary insurance amount (PIA). The disabled worker is paid 100% of their PIA, leaving anywhere from 0% to 50% of the worker's PIA to be paid to auxiliary beneficiaries (e.g. spouse, children). Eligible children can be paid up to a full 50% of the worker's PIA if they are the only child getting benefits on a disabled worker's record, but if more than one auxiliary beneficiary is eligible for benefits then they must split any available amount from the FMB. And, if only 2 children are receiving benefits and if the older child's benefits stop when they reach age 18, then the older child's benefit rate would then be added to the younger child's benefit rate.

Best, Jerry