RecruitingPhase 1Combination productAllogeneic Expanded Gamma Delta T Cells With GD2 Chemoimmunotherapy in Relapsed /Refractory Neuroblastoma or Refractory/ Relapsed OsteosarcomaThe goal of this clinical trial is to determine the maximum tolerated dose (MTD) and recommended Phase II dose (RP2D) of allogeneic expanded γδ T cells when delivered with Dinutuximab, temozolomide, irinotecan, and zoledronate in children with refractory or recurrent neuroblastoma or refractory/ relapsed osteosarcoma as well as to define the toxicities of allogeneic expanded γδ T cells when delivered with Dinutuximab, temozolomide, irinotecan, and zoledronate