A quick google gives the below info. I think you're probably best off speaking to the employee to understand their request?
"Ongoing Until Ceremony
This timeline can stretch from one week to several months depending on family circumstances, available funds, and how elaborate the ceremony will be.
Igbo traditions sometimes include a two-phase burial process for prominent elders. The first burial happens soon after death. The second ceremony, called Ikwa Ozu, occurs months or years later as a grand celebration of the person's life and achievements.
Hausa-Fulani families, following Islamic law, usually complete burial within 24 hours of death. Relatives perform the ritual washing, wrap the deceased in simple white shrouds, and place them directly in the grave without a coffin.
Afterward, families may hold fidau prayers on the third, seventh, fortieth, or even hundredth day, depending on local and family traditions."
Hi Samantha
is this purely a request to take part of normal annual leave entitlement or is there any particular bereavement leave involved too? If the former, as has been said, it’s not usually up to the employee to justify or verify the reasons for needing to take leave. But if it involves special bereavement leave it’s a bit more delicate- personally I wouldn’t be demanding evidence unless I strongly suspected it was not true. Bearing in mind that a visit all the way to Nigeria is involved anyway, so three weeks in one go is fairly reasonable in such circumstances.
Hello Samantha, this is where local context really matters. In Nigeria, burial ceremonies, especially for an elder or aged parent, are not a single-day event. They typically span one to two weeks of activities, including the wake, funeral service, thanksgiving, and family meetings to settle estate matters. These are deeply communal and often obligatory within extended family structures.
Beyond the burial itself, there are also post-burial family gatherings, legal/administrative arrangements, and cultural rites that can extend the process significantly. Add international travel logistics on top of that, and a three-week request is very reasonable and culturally consistent.
The 7-week gap between the death date and the leave start may also reflect the time needed to arrange travel, coordinate family across locations, and plan the ceremony. Nigerian funerals are often scheduled weeks in advance to allow relatives to travel from abroad.
From a cultural perspective, this would not raise any concerns for me.