A subsequent remedial measure is not admissible to prove negligence, culpable conduct, a defect in the product or its design, or a need for warning or instruction.

Fed. R. Evid. 414(d).Applicable federal or state law determines who is a "child" for purposes of Federal Rule of Evidence or comparable state rules that authorize the use of other instances of child molestation or child sex abuse against criminal defendants who are on trial for child molestation or child sexual abuse.

Cf. Treece v. Hochstetler, 213 F.3d 360, 363 (7th Cir. 2000) (holding, in plaintiff's civil rights action against police officer, police department, and city for malicious prosecution, that evidence of police officer's prior bad acts was inadmissible and properly excluded where it "did not 'bear a...That other wrongs or crimes show a person's pattern of conduct does not by itself make inapplicable either the prohibition in Federal Rule of Evidence 404(a) against the use of character or propensity to show that person's conduct on a particular occasion or the corollary prohibition in Federal Rule of Evidence 404(b) against the use of other wrongs or crimes to show character or propensity for the purpose of showing a person's conduct on a particular occasion.

Fed. R. Evid. 609.Under some circumstances untruthfulness is admissible to impeach a witness.