V.,
I'm sorry for your loss.
Cancer sucks. She was VERY young!! I'm truly sorry! May her memory be eternal!
What would **I** do for her family?
If I lived close, I would spear head meals for at least a month. I'm sure the whole family is reeling and the last thing they will be thinking of is food. When my mom was sick and after she died - their neighbors made sure that we didn't have to think of anything...nothing was frozen, it was all fresh.
I would ask him about child care and their schedule. While they are grieving the loss of their mother - routine and structure will also help them. Will he need help getting them to school? Will he need help picking them up from school?
You can set up a site like Caringbridge.com or carepages.com - this will allow people to know what's going on.
Make a memory book for the kids...pictures of their mom to help keep her memory alive. If you have any movies of her? Make sure they are put on some form of media (dvd, thumb drive, etc.) so they can watch it.
I would help him plan for the future...Christmas, New Years...if you know the family well? Ask if you can do their Christmas dinner or stockings for the kids? Give him things to help him focus on the future. Not long term - but Thanksgiving, Christmas, New Years...then let him know you and your husband are there for him....
play dates for the kids
helping with brownies (if they are involved)
Help him plan her memorial or celebration of life.
If you know a financial planner? Recommend him/her. IF you are close? Make sure the life insurance (if she had any) is notified (sit with the husband and make a list of life insurance policies, credit cards, bank accounts, 401K, etc).
This is why a financial planner would be a great asset right now - life insurance policies, trusts, bank accounts, credit cards....oh my - in California?! If she's being cremated - prepare for several weeks of waiting - permits need to be obtained in order to cremate her. Since he has two young children? However morbid this sounds? Make sure he has a will in place as well as people selected to take care of the children should something happen to him. No, it's not something you want to talk about RIGHT NOW - but really? This is life. SH*T happens.
Help him go through her things at a later date. My mom has been dead 7 weeks - my dad is getting ready to go through her side of the closet. He's not there yet, but he's close. HE brought it up to my sister...not the other way around...
Hope this helps. Again, I'm sorry for your loss!!