Does the trial court erred in failing to instruct the jury on the definition of primary caregiver?

In this case, we need not, and do not, reach the issue of whether the trial court erred in failing to instruct the jury on the definition of primary caregiver. As we will explain, any error in failing to give such an instruction was harmless under the applicable standard set forth in Chapman v. California (1967) 386 U.S. 18, 24 [17 L.Ed.2d 705, 710-711]. (See People v. Sengpadychith (2001) 26 Cal.4th 316, 324 ["a trial court's failure to instruct on an element of a crime is federal constitutional error [citation] that requires reversal of the conviction unless it can be shown 'beyond a reasonable doubt' that the error did not contribute to the jury's verdict" (italics omitted)].)