self employed family leave--Grandchild!!

I took time off from self employment to take care of my grandchild so that my daughter could work.  I qualify for the self employed family leave credit (school closed, ....) except no where does it define "child".  I do not otherwise support my child or grandchild.  I just helped out because I could take time off and she could not.   If child includes grandchild, I can take it.  If not, then I can't.  Most places in the tax law, child includes grandchild but I could not find any info dealing specifically w the self -employed family leave credit.  thoughts please.