Mombasa came under the control of the sultan of Zanzibar in 1840 and was leased to the British in 1895. From 1905 to 1907 it was the capital of the British East Africa Protectorate. In 1920 it became capital of the British Protectorate of Kenya.
“Twin cities
Mombasa is a sister city of:
Seattle, Washington, USA
Honolulu City and County, Hawaii, USA[15]”
I wonder if his Mom was involved somehow with this twin city program or maybe his Kenyan father. That might explain the visit to Mombasa, while they were in Kenya.