If your kids are not biologically related, then they are not at increased risk. However, if they knew your nephew or niece, that would change the risk.
There are several risk factors for suicide including: 1) family history (genetic) of suicide, or 2) knowing anyone (friends, family) who has committed suicide.
Keep a close eye on them and if you ever see any signs of depression (or other mental/emotional issues) have them evaluated.
I hope this answers your question...let me know I can be of further assistance. Take care.
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