Template.lesionTableTimepointCell.helpers({ 'longestDiameter': function() { // Search Measurements by lesion and timepoint var lesionData = Template.parentData(1); if (!lesionData || !lesionData.timepoints || !lesionData.timepoints[this.timepointID]) { return; } return lesionData.timepoints[this.timepointID].longestDiameter; } });