folding the musalla

Q: I heard this from someone. Wanted to know if it is authentic

1. Imam Ahmed bin hambel said "tell your child to offer prayer and keep doing this for three days. If he doesn't listen, kill him on the 4th day.

2. Fold the ja-e-namaz/musalla/praying mat after you finish praying otherwise shaitaan comes and sits/prays on it.

Q: Is it necessary to fold the corner of the jahe namaaz when it is not being used? I have heard some people say it is an innovation but most of my relatives do it.