If the alleged father is not available to be tested, forensic DNA testing can be considered using items which may contain the alleged father's DNA. Forensic DNA testing can be performed any anything that has biological material from the father such as an old toothbrush, electric razor, blood stains, saliva stains, and bone or teeth from an exhumation.
If it is not possible to obtain a forensic sample for the alleged father, testing his direct relatives can be considered. If the alleged father's parents are available, the DNA Grandparent Test or DNA Grandparentage Reconstruction Test can be performed. If the alleged father has any siblings, then a DNA Aunt/Uncle can be performed. If the alleged father has other children, then a DNA Sibling Test.