My husband was estranged from his parents for many years. He reached out to them when he was diagnosed with a terminal illness. They didn’t have enough time to discuss and resolve their past, but they were at peace with each other when he died. Now my husband’s parents wish to keep in touch with me and my toddler-age son, as he is the only link they have to their only child. The problem is that my son is not my husband’s biological child. I had an affair, the biological father dumped me upon realizing I was pregnant, and my husband (to cut the complicated story short) decided to raise the baby as his own. He didn’t legally adopt our son—we simply put his name on the birth certificate and that was that—or tell anybody other than our marriage therapist. It was a painful, regretful, and humiliating episode of my life and I do not wish to tell even my own parents. But I feel incredibly guilty whenever my in-laws talk to me about how grateful they are to have a grandchild to remember their son, or make comparisons between my son and my husband when he was at a similar age. I feel like I need to come clean with them before they develop a strong attachment to him. They are already talking about changing their will to include their “grandson.” What should I do?