A trans-humanist group might be more likely to have access to a time machine than most other groups, but I still don't think it is very likely that joining the

A trans-humanist group might be more likely to have access to a time machine than most other groups, but I still don't think it is very likely that joining the group caused them to become a first-born child. It is much more likely that if there is a causal relationship, being a first-born child caused them to be more likely to join the group.