We've adopted. I don't know how different things are with a SGO.
Our LA has an 'Information Exchange' coordinator who checks and sends on letters.
We have a letterbox agreement which states frequency of letters and whether photos & cards will be accepted. We send first, as then it prompts BM to respond.
I agree yours seems a bit informal, I'd ask for a more formal letterbox agreement to regularise things.
re fairly poorly
We go with honest but optimistic. We don't want to leave BM with 6 months of worry, but neither do we want to hide important things either.
So e.g.
LO has been quite poorly in hospital with pneumonia but is on the mend now and we hope to have him home soon.
In the letter we cover: development, health, character, likes/dislikes
So for a little one stuff like this:
LO started walking in June last year. He now toddles around happily , only occasionally tripping over his feet. He has started saying a few words including 'car' and 'moo' and 'juice'. He sleeps well at night and is a bundle of energy during the day.
LO likes feeding the ducks at the park and kicking a ball around. He loves Paw Patrol and has a toy Rosie dog that he sleeps with. His favourite meal is spaghetti hoops with extra cheese followed by mashed banana. He tries to feed himself but without much success so far!
He hasn't got much understanding yet, but we do chat to him about you, which we will continue to do as he grows up. We get out his special photo book and he points and says 'Firmum' (first mum) when he sees your picture.
hth