Foster children have to qualify the same as other children. In general, to be a taxpayer's qualifying child, a person must satisfy four tests:
Since the foster child did not live with you for more than one half the year the child does not qualify to be your dependent.
Neither would this child be a qualifying relative since the person must:
Live with you all year as a member of your household, or
Be related to you
I hope this helps even though it is not likely the answer you wanted to hear.
Best regards; and thank you for opening your home and family to care for the child.
You are quite welcome.