YYY to all the above about Robert! I love Robert. He and Lyndie (as nobody else refers to her, another thing I love) previously lived in Sunningdale. He used to have his own IT company but that went bust. Prior to that, Lynda didn't have paid employment but she managed to get a receptionist job at Grey Gables while they were trying to rebuild their finances. Now they run a B&B from Ambridge Hall as well, with Robert figuring largely in the running, and he also does a bit of handyman stuff (or did, it's not been mentioned for a long time).
L & C are the children of his earlier (failed) marriage to someone else, who as far as I can recall has never featured in TA. I think (but may have made this up) that Lynda used to be Robert's secretary. Surely she wasn't the OW! As far as I can recall, this has never been spelled out, but I hope not.
She desperately wanted to have children, but couldn't, which has been a great sadness for her. Very well handled long-term storyline, I would say.
Leonie is married to James Bellamy, Lilian's son. They have a very young son who I think is called Mungo. Coriander has a young child too, but I can't even remember whether girl/boy, let alone age, name of father or anything else. 