Sounds so very 'American' to worry about these things (and haunting).
Any place with history will have seen death.
Most houses around here are Victorian, people will factually have died in many of them. Many of my family members died at home. Some natural causes (from my Great-grandma dying in her sleep, my Nana who died of a sudden heart attack, my uncle who died of diabetes in his sleep, to my baby cousin who died of SIDs), a couple from suicide and even one murdered (domestic violence).
Family still live in several of those houses and the people who eventually bought the 'murder' one likely had no idea (its not like it made news, it was buried real quick by police). No one advertises that the previous owner had her head smashed in by her drunk boyfriend.
Future buyers wouldn't have know that my baby cousin died in that house either etc... when it came time to sell. In the UK 200 children a year die of SIDs and thats now, historically it was much higher so living in a house a child died in is really not that rare.
just a little statistic in the UK per year 52 children are murdered and 182 women are in domestic violence attacks most of which occur at home.
The house opposite us is for sale, this owner got a bargain because the previous one committed suicide in the house two decades ago. I doubt they plan to tell the new buyer the last owner hung themselves in the master bedroom.
You're overthinking it purely because you know but its likely far more common than you ever considered.