The purpose of this study was to examine the extent to which typically developing (TD) siblings of children with autism spectrum disorder (ASD) could implement the model-lead-test (MLT) strategy through the self-monitoring checklist and telehealth-based coaching, as well as the impact of the sibling-mediated intervention on the acquisition of various skills in children with ASD. Two sibling dyads participated in this multiple-probe-across-behaviors study. The instructors coached and provided feedback to the TD siblings on using the MLT strategy and the self-monitoring checklist via telehealth. The results demonstrated that the self-monitoring checklist and the telehealth-based coaching effectively improved treatment fidelity as the TD children delivered the target strategy, which, in turn, improved a diverse range of skills in their siblings with ASD. However, difficulties in generalization to new instructional targets for TD participants and maintaining learned targets for participants with ASD were observed.