[FMergeEmitterResults](API\Plugins\Niagara\INiagaraMergeManager\FMergeEmitterResults) MergeEmitter ( const [FVersionedNiagaraEmitter](API\Plugins\Niagara\FVersionedNiagaraEmitter) & Parent, const [FVersionedNiagaraEmitter](API\Plugins\Niagara\FVersionedNiagaraEmitter) & ParentAtLastMerge, const [FVersionedNiagaraEmitter](API\Plugins\Niagara\FVersionedNiagaraEmitter) & Instance ) const