Our grandson is getting married. The brides family is very wealthy while we are of meager income. Is it proper to give a modest gift of money or more proper to give a gift?

Her family's wealth (or perceived wealth) shouldn't have a place in what you decide to give. Money is always nice for the couple can use it on the honeymoon, home, etc. Gifts are always fine as well.

It really depends on you and what you can afford. I was just married in June and the fact that my grandfather even came was a HUGE gift and blessing to us. :)

My former mother-in-law was on a very limited income and when her children married, she sewed each of them a quilt. What you spend is not important so do not let yourself get dismayed at that. When I got married I even put a small note in my invitations that gifts were optional, not necessary, I just wanted to see my relatives there to share my happiness.