In Bold Color Bootcamp, Charla talks about starting off portrait painting by using a stranger as a subject. Painting loved ones is extremely sensitive and puts a lot of pressure on the process, particularly as new artists. Learning, in our opinion, is not the time to paint someone you know. This is not only true of relatives, but even of famous celebrities. When painting a recognizable face, an artist is apt to become hyper-critical of the similarities and differences in their work rather than simply focusing on the learning process.
If you consider yourself an experienced painter you may choose a subject you know, but if you are a beginner, it is wise to choose an unknown subject.