ANOTHER no gift question

There is one family from whom we never received a gift OR card from. This is a family I was extremely close to growing up - I went to elementary school and high school with the girl, and my mom is friends with her parents.

I did all the thank yous, and said Thanks for coming, it was great to see you again, etc, but I said nothing about any gift. TY's were sent out weeks ago, and I havent heard anything from them.

Can I assume this means that they didnt give us anything?
Because they would know that if a gift is NOT mentioned in the TY that one was not recieved??

Is this common knowledge, or just common among brides?

no, don't assume they got the hint.

Some people do NOT mention the gift at all in TY cards. My IL's have close friends of the family who are notorious for only writing 'I am glad you were able to celebrate my _____ with me' no matter what you give them. I know they receive our gifts because I write checks, and the checks always get cashed by them. I've even looked at the endorsement to see if the signature matches their writing and it's DEFINITELY them cashing the checks.

Guests do have 1 year to give a gift. My last gift arrived 2 months after my wedding.

Although, DH has 1 aunt who STILL says that 'next time we visit, we'll go shopping and pick out your wedding gift'

I received cash in a letter envelope... no card, no name nothing!