...and then there's this:
http://nationalpost.com/health/a-washington-couple-took-a-paternity-test-for-their-child-the-man-of-the-pair-wasnt-the-father-his-unborn-twin-was...
According to Starrs research into the matter, the babys mysterious origins are a product of the genetic phenomenon of chimerism, in which one fetus that dies early in pregnancy is subsequently absorbed by the remaining sibling. This process, called vanishing twin phenomenon, is believed to be much more common than people think: a 1998 study found that one out of every eight single births begins as a twin or other multiple at conception.
The vanishing twin effect occurs when, instead of producing twins, two zygotes fuse into one. Starr believes that this is what happened to the Washington man, who ostensibly absorbed some of his fraternal twins cells while in the womb, becoming a chimera a spectral blend of himself and his unborn brother.
One in eight!? Maybe those 3 boys were his sons? ...or at least his absorbed chimeric unborn brother's sons.
That's possible, there's an example of a woman who gave birth to her twin's daughter even though she never had a twin. She was her own twin.
https://www.opposingviews.com/i/health/womens-health/woman-gives-birth-children-discovers-her-twin-actually-biological-mother-sheA Washington state woman was shocked when she was told that the children she gave birth to were not her own. It turned out that her twin was actually the biological mother of her children, and this only led to more confusion because she didnt have a twin. In the end, it was discovered that the woman was in fact her own twin, confirmed by doctors to be a rare medical condition.