"This morning," Serena says. She doesn't want to reveal all of the details but sooner or later they'll speak for themselves. "I had a caesarean about a week ago."

At the offer of a cab, she nods, relieved that there's no mention of some app she needs to call for it. If it's simply a matter of dialling a few numbers she can probably do it herself, but the company is probably needed. "And if you wouldn't mind. The doctors mentioned needing help but I'm afraid my husband isn't with me."

Nor her son, just a few floors up but feeling an age away.