Military ladies

My husband is in basic for thanksgiving so I am wondering what I can and can’t send. I was thinking of a letter with a picture of me, our son, and dog together in the letter but is there anything I add to that? I don’t want him getting in trouble but I don’t want to miss the opportunity if others are getting sent stuff and he’s left out :( please tell me what’s allowed and what won’t get his entire unit in trouble.