In addition to asking questions of those she interviews with, I suggest asking for an opportunity to talk with future peers. Often, they can provide valuable insight on what the real company culture is. Here are some other tips:
Take a look around the office, does she see any indicators of parents such as proudly displayed young artwork?
Ask about success- does the company know how to measure productivity? Or does the person who "puts in the hours" succeed?
What is a typical day like? If everyone works from 7am-7pm, it is not going to be family friendly.
Check out the leadership in the company. Are all higher ranking executives men? Lack of female leadership is a good indicator that the company may not be friendly to working moms.
I hope this helps. My book about this topic was just released- would make a great gift for your friend!
(The Parent's Guide to Family Friendly Work, Career Press).
Lori K. Long