House purchase question, regarding joint tenancy

[Roland Chan]

I am in escrow of purchasing a house, the house is owned by two brothers (A and B), in form of joint tenancy. Now all the purchase contract is signed by brother A only. Escrow said brother B will grant deed to A at closing, then A will grant deed to me. It seems logical, but how do I protect myself? I feel not comfortable as the purchase contract only has one person's signature while the house is owned by two people. Is that normal practice?

Now the preliminary report shows the house is owned by two brothers in joint tenants, will the title insurance protect from any mistake happen in "B grant deed to A"?

Thanks~