Because if you were already married, and yet your new 18 year old plaything wife wanted to see your country, would you take her to your village, or to the opposite side of the country, knowing she would never run into your real wife there while at the supermarket. Probably Mombasa had a nice beach.
She's 9 months pregnant and about to pop. And they're wandering around the coast sightseeing and lying on the beach? Also, who would fly halfway around the world in that condition? In 1961, would airlines even allow a woman who's that close to giving birth to take a flight like that? How many hours would a flight from Hawaii to Kenya even be?