Well, if this little one was born at 24 weeks (and a twin at that), he or she won't be wearing any outfits for a long time. My little one was born at 27 weeks, but he was about the size of a 23 weeker (1 lb and 7oz) due to some growth issues. For the first two months or so he was on a ventilator and had about 8 million tues, wires, monitors, IVs, etc in every possible spot on his body. He couldn't wear anything at all. And, even when he got a little stronger and some of that stuff was disconencted, he was still too way to little for the preemie outfits from the stores. Those are made for babies in the 4 to 5 pound range, mostly. Paul came home from the hospital at just over 3 months old, weighing 3lb and 10oz. We had to special order all his clothes for a while! Something special that they could save for later might be nice, though.
Flowers for mom would be nice. And food, as mentioned. One thing I appreciated was a big basket of crossword puzzles, books, magazines, etc. Paul was in the hospital for just over 3 months, and I spent about 8 hours at his bedside every single day of that! Reading material saved my life!
As for the cards, that's tough. I remember being bitterly disappointed when Paul was born that all around me in the hospital were mothers getting flowers and candy and happy cards and stuffed animals - and I was getting sympany and "thinking of you" cards. Yes, my baby was very sick, but I still wanted to celebrate his birth. I was still glad I had him! I remember to this day the few people that sent me "normal" new baby cards and gifts - and I still appreciate it. Of course, the death of the other baby makes your friends situation different. I'm not really sure what would be the best way to handle that . . .
The road in the NICU, especially for a very tiny and sick baby, is long and very, very scary. Those first few weeks are like living perched on the edge of a cliff, just waiting for the phone call or news from the doctor that will push you over the edge. I know you said you aren't close friends, but I do think it's great that you want to reach out to this woman and her family - even in a very small way. She's going to need it.