She might only have been 4 or 5 months pregnant when when went TO Kenya. Her whereabouts during this time frame are very obscure. She may well have gone much earlier in the pregnancy, stayed too long. She was fascinated enough by an exotic to let him impregnate her, surely she was fascinated enough to want to see Kenya.
If they went to Kenya they could have gone after early May when UH ended sessions, placing her at about 6 months pg of course we don’t know if Obie jr was full term (or if he will complete his full term either).
People back in Hawaii didn't know there was a baby on the way and didn't see him until he was a month old. If not in Hawaii, where was Ann and her baby bump?