As demonstrated on the etiquette deal breaker thread, thank you notes are apparantely very hard for some people. FI and I have now sent two gifts to FBIL and FSIL for their new baby (he will be a year in September). They live out of state, so I am always extra careful to get a tracking number on the packages.
Each time, the package shows delivered with no word from FSIL and FBIL for about a week (I like to give them the benefit of the doubt that the thank you card is in the mail). We literally have to call them to confirm that they got the package only to be responded to with "oh yeah it came last week. Thanks!" Listen, I get that they had a new baby and that this is a busy time in their lives, but come on, people! Is it that hard to even send a quick text letting someone know that their out of state package was received? Apparently it is...Thanks for listening. I feel better now.