The Mystery of the White Elephant (Three Cousins Detective Club)

is #1 in the Three Cousins Detective Club series.
==Book Description==
In The Mystery of the White Elephant, a swap meet is taking place at Timothy Dawson's church, and the three cousins are hoping to find the perfect "white elephant" gift to buy. When a cookie jar mysteriously disappears, Timothy, Titus, and Sarah-Jane decide it's a job for the "TCDC"! The problem is, who in the world would steal a white elephant?
(Description from paperbackswap.com)