DH's friend and his DW lost their DD aged 10 some years back. The DD had been severely disabled from birth and her condition was life limiting, so it was something they had long been dreading, but obviously that didn't reduce their pain. Since then DH has always phoned his friend on the anniversary of her death for a chat, to show that we remember her too. Recently the friend happened to mention that they had gone over to marking her birthday rather than the day of her death, which makes sense. We did a bit of checking and realised that the 18th anniversary of her birth will be at the end of January. We'd like to send a card but are really worried about the wording - there seems a lot of scope for saying something that could be hurtful or tactless.
We know the kind of card we'd like to send (with a flower on the front that meant a lot to them), but can anybody give us some tips for the content? I've done a bit of Googling on bereavement sites and it's just made me more worried, because people are giving stories about how someone wrote/said something awful and upset them.