A friend recently threw a housewarming party, and I was mortified when I arrived and discovered that I was the only person who had not brought a gift! What should I do?
Don't worry! The omission of a gift probably bothered you far more than your friend. And it's not too late to send something now. Don't apologize or belabor the fact that you didn't bring a gift to the party. Just send your gift with a gracious note and everything will be just fine.

I will be staying at a friend's home for the weekend. Is it OK to send a gift after my stay?
Yes. As a houseguest, it's perfectly fine to bring your gift with you, or send it-along with your thank you note-after you've left.

How long do I have after attending a wedding to send a gift?
One year.

I forgot my friend's birthday. What should I do?
In an ideal world, we would remember to call everyone on his birthday or send a card so that it would arrive on the actual day. Unfortunately, we sometimes fall short of this goal. Many people extend their birthday into a week-long celebration. You can send a "belated" or traditional card and gift, and still downplay the fact that's it's late. Most people will simply be pleased with the thought, and not concerned that you're late.