Don't worry! The B4/B4A Personal Effects Accounting Documents are for items you own, not cash.
You only need to declare funds if you are carrying more than $10,000 Canadian or equivalent (in the form of cash, securities in bearer form including stocks, bonds, debentures, treasury bills or negotiable instruments in bearer form including bankers' drafts, cheques, travelers' cheques or money orders).
If you wire the funds (which most people prefer to do, rather than carrying the currency since it can't be stolen on the way), then the banks handle the reporting for you of the transaction if you send more than $10k at once.
Either way, you don't need to pay taxes on the money you are moving itself when you import it (although you will of course have to declare future income on the money ... interest, capital gains, whatever depending on the specifics) and as long as you got the money legally you should be fine
Your husband can keep his B4 for the wonderful gift he'll get for your baby before landing 8)