Basically Epigenetic studies how environmental factors can modify the DNA. The fascinating part of it is to study how experiences can actually not only have effects on our health and psychological well being but on our children's health and psychological well being as well. Stress, depression, negative life experiences will have deep effects on our DNA and will actually keep harming the next generation... The positive points is that DNA can be fixed, simply by solving the issues...
https://bscb.org/learning-resources/softcell-e-learning/epigenetics-its-not-just-genes-that-make-us/ for example as it is quite a simple article...
''Even more surprisingly, some data seems to suggest that grandchildren of women who were pregnant during the Hunger Winter experience some of these effects. From what we have already discussed, this strongly suggests an epigenetic mechanism. In fact, research with the Dutch Hunger Winter families continues, and a recent study looking at a gene galled IGF2 found lower levels of the methyl tag in the DNA of this gene in individuals exposed to the famine before birth. Although IGF2 may not itself be involved in the increased risk of poor health in these people, it shows that epigenetic effects (i.e. reduction of the number of methyl tags on particular genes) that are produced before birth can last for many decades. Studies in animals have also found that the diet of the mother can have effects on her offspring. For example, feeding sheep a diet lacking the types of food required to make methyl groups leads to offspring with altered patterns of DNA methylation and which have higher than expected rates of certain health problems.''