Im sure Claire is happy for you, and whilst she may be happy with her weight now, perhaps when her family is complete she might look to a permanent weight loss solution herself. Im sure Claire would qualify for WLS if she wanted it. Maybe when she see's how well you are doing she may consider it for herself.
As for your mum, you will probably never know why she chooses not to mention it - same with me and D, but just hold your head high, focus on the end result and you will have the last laugh in a month or two when you are offering her your size 18s as "they are hanging off me mom, but you should manage to get into them..."