What has been observed about offspring of all organisms for thousands of years?

The fossil record confirms reproduction only “according to their kinds”. The Bible account in Genesis says, ‘Domestic animal and wild beast according to its kind’.
Yet greater difficulties for evolutionary theory involve the origin of the complete genetic code​—a requirement for cell reproduction.
They are, so to say, "a chip off the old block". A product of their DNA or genetic code.
Further research see jw.org