It is a personal decision. I recommend you talk it over with your therapist.
Also, confirm what the pharmacy tech requirements are in your state and what the starting pay rate is.
If you can work, I think that you should try it.
While your family is taking care of your expenses now, something could happen in the future that makes then unwilling or unable to pay your expenses. If you are babysitting for family now, what happens when the child(ren) grow up & no longer need a babysitter? Will they still be willing to support you? What if they disagree with what your expenses should be (that they are covering)?
You will also earn SSDI credits by working a pharmacy tech job.