-snip-
I wanted to say that typing the seed phrase it showed the password (the one I had).
But it didn't show me the Wallet ID or any other information of the account, so I guess the only help I can get to follow on is from their support desk. I sent them an e-mail let's see what they say...
On a side note, you must use the owner's (
your mom's?) email to contact their support, that alone is a strong evidence that the account you're referring to belongs to you/your mom.
It's based from this 'web archive' of the recovery page, they only require the email associated with the account:
https://web.archive.org/web/20140322014105/http://blockchain.info/wallet/forgot-identifier(
do not enter your email there, it's only a copy of the old page)
