Another feeling for Jessica. I'm inferring from the article that she has moved away, given that Tony and Joan "travelled" to tell her the news. What a shock that must have been. And whilst Joan says Jessica will always be her daughter, she's embraced Claire - going on holiday together, spending Christmas together and they don't live too far apart. I guess Joan and Jessica's relationship wasn't all glitter and sparkle and Joan gets another go with a "new" daughter.
No mention of the other two sons/brothers, I wonder what they make of it.
Claire gets welcomed into a warm, loving family. Jessica doesn't have that - no biological siblings, biological mother dead, no mention of the father. And effectively replaced in the family she's known for 55 years.
This isn't "we've found a half sibling we didn't know about" or "the baby mum had to give up before meeting dad", both of which add to an existing family. It's "here's our proper sister", the original sister doesn't belong.