All that resting must have taken it's toll, she needs a holiday.
I took a holiday when I was 4 months into the pregnancy - my due date was at the beginning of July, so it was around the same time of year than it is now. And I'm glad I had that time! For the pregnancy was difficult, my son came 1 month early, I had mastitis and he was sickly through his first year... in hindsight it was the best descision I ever made!
And if Catherine feels up to travelling, she should do so and gather strength on holiday. And should not worry about people who are simply envious as if their negative feelings would change a thing except hurting the envious person herself.