Question on I-485 and EAD ???

I am on H-1 visa and have got I-140 approval. Could anyone help me answer the following questions?

1) If I use EAD to work, will I lose H-1 status?
2) If my son (a high school student and needs a driver license) applies for an EAD (for social security number purpose), does he lose H-4 status?
3) Is there any minimum age limitation for EAD application?

Thank you very much!!!