Your girl friends -- friend has NO idea what she is talking about
Gee wiz - with friends like that , who needs enemies !
We have had Dobermans since 1981 and have never had one turn on us . As time goes on , they are so attached to you it's unbelievable - they are and will be your best friends ill there last breath -
As far as your son and your Dober - they will have a unbreakable bond , if they do anything together , play ball , sleep together , you name it , What I have seen is that Dobermans do get protective of kids - they protect them .
I'm not saying a 100 % it can't happen - if it did , it would be a one in a million .
If you got your Dober from a reputable breeder - then I would really never have a concern , Really , maybe the best thing to do is call your breeder and tell them what you had heard - hearing from them might settle things down better than getting info off the internet .
Best of luck !