I know that's a sea of 'no', but those were very good questions. Kudos.) aahhahahahaha many thanks...as someone said "it is useful also to rule out things"

So...child's death = mother not the murderer? Mother not guilty? Was there any murder at all? Or just a suspect of murder? Did the child relevantly have a brother/sister? Did the brother/sister die before him? At the same age? If it was also in the same circumstances...is it a genetic disease? Was he/she the Siamese twin of the other who died later on? Just twin?
died for an accident = something that could be avoidable if the ones who took care of him had payed more attention? did he contract a disease? did he fall from somewhere? Did he touch a power outlet? did he play with something dangerous (e.g. a knife)? Did he eat something he had not to eat? Allergy relevant? Cold? dehydration?
Had the child been in his room, fed in a good way and without possibilities to exit his room (e.g. he was in a bed with high guardrails), would he die? If so...was him kind of suicidal?
the mother of the child was in prison without the child who was under foster care...is it possible that the child died because he needed to be breastfed just by the mother? Or somehow due to the "distance" from the mother?