What is the test for blood tests in divorce proceedings?

[13] The respondent argues that the applicant is estopped from seeking blood tests by reason of his failure to do so from separation until this motion. The only case to which I have been referred by counsel is Young v. Young, 1987 CanLII 2941, 10 R.F.L. (3d) 337, [1987] B.C.J. No. 2157, 1987 Cars­well­BC 538 (B.C.C.A.). As summarized in the headnote “Pursuant to a decree nisi in 1973, the husband was ordered to pay child support. The husband paid nothing on the order and the wife unsuccessfully attempted to enforce the order in 1975 and 1979. In 1979, the husband applied to terminate child support but child maintenance was reserved under the order. The child, now almost 16, had health and learning problems and needed special training to become independent. The wife applied to vary the divorce order to make provision for child support..” and at that time, the husband raised the issue of paternity.